78737715220 has 24 divisors (see below), whose sum is σ = 166812474024. Its totient is φ = 31216367616.

The previous prime is 78737715169. The next prime is 78737715227. The reversal of 78737715220 is 2251773787.

It can be written as a sum of positive squares in 4 ways, for example, as 201015684 + 78536699536 = 14178^2 + 280244^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78737715227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17417589 + ... + 17422108.

It is an arithmetic number, because the mean of its divisors is an integer number (6950519751).

Almost surely, 2^78737715220 is an apocalyptic number.

It is an amenable number.

78737715220 is an abundant number, since it is smaller than the sum of its proper divisors (88074758804).

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

78737715220 is a wasteful number, since it uses less digits than its factorization.

78737715220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34839819 (or 34839817 counting only the distinct ones).

The product of its (nonzero) digits is 1152480, while the sum is 49.

The spelling of 78737715220 in words is "seventy-eight billion, seven hundred thirty-seven million, seven hundred fifteen thousand, two hundred twenty".