78309504 has 320 divisors, whose sum is σ = 290283840. Its totient is φ = 20404224.

The previous prime is 78309487. The next prime is 78309523. The reversal of 78309504 is 40590387.

It is a super-2 number, since 2×78309504² = 12264756833452032, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 943447 + ... + 943529.

It is an arithmetic number, because the mean of its divisors is an integer number (907137).

Almost surely, 2^78309504 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 78309504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (145141920).

78309504 is an abundant number, since it is smaller than the sum of its proper divisors (211974336).

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

78309504 is a wasteful number, since it uses less digits than its factorization.

78309504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129 (or 108 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 78309504 is about 8849.2657322515. The cubic root of 78309504 is about 427.8302526558.

The spelling of 78309504 in words is "seventy-eight million, three hundred nine thousand, five hundred four".