78365939944 has 8 divisors (see below), whose sum is σ = 146936137410. Its totient is φ = 39182969968.

The previous prime is 78365939929. The next prime is 78365939959. The reversal of 78365939944 is 44993956387.

It is an interprime number because it is at equal distance from previous prime (78365939929) and next prime (78365939959).

It can be written as a sum of positive squares in only one way, i.e., 78365283844 + 656100 = 279938^2 + 810^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×78365939944² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 78365939944.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4897871239 + ... + 4897871254.

Almost surely, 2^78365939944 is an apocalyptic number.

It is an amenable number.

78365939944 is a deficient number, since it is larger than the sum of its proper divisors (68570197466).

78365939944 is a wasteful number, since it uses less digits than its factorization.

78365939944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9795742499 (or 9795742495 counting only the distinct ones).

The product of its digits is 176359680, while the sum is 67.

The spelling of 78365939944 in words is "seventy-eight billion, three hundred sixty-five million, nine hundred thirty-nine thousand, nine hundred forty-four".