78345920 has 56 divisors (see below), whose sum is σ = 188451744. Its totient is φ = 31021056.

The previous prime is 78345901. The next prime is 78345929. The reversal of 78345920 is 2954387.

It is a super-2 number, since 2×78345920² = 12276166361292800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78345929) 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 7 ways as a sum of consecutive naturals, for example, 31772 + ... + 34148.

Almost surely, 2^78345920 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78345920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94225872).

78345920 is an abundant number, since it is smaller than the sum of its proper divisors (110105824).

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

78345920 is a wasteful number, since it uses less digits than its factorization.

78345920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2497 (or 2487 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 38.

The square root of 78345920 is about 8851.3230649435. The cubic root of 78345920 is about 427.8965598569.

The spelling of 78345920 in words is "seventy-eight million, three hundred forty-five thousand, nine hundred twenty".