78736520 has 64 divisors (see below), whose sum is σ = 189831600. Its totient is φ = 29286400.

The previous prime is 78736501. The next prime is 78736529. The reversal of 78736520 is 2563787.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 7941124 + 70795396 = 2818^2 + 8414^2 .

It is not an unprimeable number, because it can be changed into a prime (78736529) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 59870 + ... + 61170.

Almost surely, 2^78736520 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 78736520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94915800).

78736520 is an abundant number, since it is smaller than the sum of its proper divisors (111095080).

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

78736520 is a wasteful number, since it uses less digits than its factorization.

78736520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1418 (or 1414 counting only the distinct ones).

The product of its (nonzero) digits is 70560, while the sum is 38.

The square root of 78736520 is about 8873.3601301874. The cubic root of 78736520 is about 428.6064858095.

The spelling of 78736520 in words is "seventy-eight million, seven hundred thirty-six thousand, five hundred twenty".