405121920 has 256 divisors, whose sum is σ = 1512276480. Its totient is φ = 90316800.

The previous prime is 405121903. The next prime is 405121939. The reversal of 405121920 is 29121504.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 577570 + ... + 578270.

It is an arithmetic number, because the mean of its divisors is an integer number (5907330).

Almost surely, 2^405121920 is an apocalyptic number.

405121920 is a gapful number since it is divisible by the number (40) 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 405121920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (756138240).

405121920 is an abundant number, since it is smaller than the sum of its proper divisors (1107154560).

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

405121920 is a wasteful number, since it uses less digits than its factorization.

405121920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 773 (or 761 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 24.

The square root of 405121920 is about 20127.6406963161. The cubic root of 405121920 is about 739.9378569681.

The spelling of 405121920 in words is "four hundred five million, one hundred twenty-one thousand, nine hundred twenty".