78752635641 has 15 divisors (see below), whose sum is σ = 117646599103. Its totient is φ = 52500073320.

The previous prime is 78752635639. The next prime is 78752635669. The reversal of 78752635641 is 14653625787.

The square root of 78752635641 is 280629.

It is a perfect power (a square), and thus also a powerful number.

78752635641 is a `hidden beast` number, since 7 + 8 + 75 + 2 + 6 + 3 + 564 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1812971241 + 76939664400 = 42579^2 + 277380^2 .

It is not a de Polignac number, because 78752635641 - 2¹ = 78752635639 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (78752634641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 2510071 + ... + 2541251.

Almost surely, 2^78752635641 is an apocalyptic number.

78752635641 is the 280629-th square number.

78752635641 is the 140315-th centered octagonal number.

It is an amenable number.

78752635641 is a deficient number, since it is larger than the sum of its proper divisors (38893963462).

78752635641 is an frugal number, since it uses more digits than its factorization.

78752635641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62374 (or 31184 counting only the distinct ones).

The product of its digits is 8467200, while the sum is 54.

The spelling of 78752635641 in words is "seventy-eight billion, seven hundred fifty-two million, six hundred thirty-five thousand, six hundred forty-one".