78575641640 has 32 divisors (see below), whose sum is σ = 176815365480. Its totient is φ = 31426670592.

The previous prime is 78575641619. The next prime is 78575641699. The reversal of 78575641640 is 4614657587.

It can be written as a sum of positive squares in 4 ways, for example, as 13114372324 + 65461269316 = 114518^2 + 255854^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 257984 + ... + 472976.

Almost surely, 2^78575641640 is an apocalyptic number.

It is an amenable number.

78575641640 is an abundant number, since it is smaller than the sum of its proper divisors (98239723840).

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

78575641640 is a wasteful number, since it uses less digits than its factorization.

78575641640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 224141 (or 224137 counting only the distinct ones).

The product of its (nonzero) digits is 5644800, while the sum is 53.

The spelling of 78575641640 in words is "seventy-eight billion, five hundred seventy-five million, six hundred forty-one thousand, six hundred forty".