345405720 has 256 divisors, whose sum is σ = 1220935680. Its totient is φ = 77299200.

The previous prime is 345405719. The next prime is 345405721. The reversal of 345405720 is 27504543.

345405720 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (345405719) and next prime (345405721).

It is a super-2 number, since 2×345405720² = 238610222817436800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (345405721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 940977 + ... + 941343.

It is an arithmetic number, because the mean of its divisors is an integer number (4769280).

Almost surely, 2^345405720 is an apocalyptic number.

345405720 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 345405720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (610467840).

345405720 is an abundant number, since it is smaller than the sum of its proper divisors (875529960).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

345405720 is a wasteful number, since it uses less digits than its factorization.

345405720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 446 (or 442 counting only the distinct ones).

The product of its (nonzero) digits is 16800, while the sum is 30.

The square root of 345405720 is about 18585.0940272036. The cubic root of 345405720 is about 701.6327329469.

The spelling of 345405720 in words is "three hundred forty-five million, four hundred five thousand, seven hundred twenty".