78637238520 has 128 divisors (see below), whose sum is σ = 238441320000. Its totient is φ = 20745420800.

The previous prime is 78637238489. The next prime is 78637238543. The reversal of 78637238520 is 2583273687.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23620216 + ... + 23623544.

Almost surely, 2^78637238520 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 78637238520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (119220660000).

78637238520 is an abundant number, since it is smaller than the sum of its proper divisors (159804081480).

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

78637238520 is a wasteful number, since it uses less digits than its factorization.

78637238520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5393 (or 5389 counting only the distinct ones).

The product of its (nonzero) digits is 3386880, while the sum is 51.

The spelling of 78637238520 in words is "seventy-eight billion, six hundred thirty-seven million, two hundred thirty-eight thousand, five hundred twenty".