78421171065 has 32 divisors (see below), whose sum is σ = 127092979200. Its totient is φ = 41287760640.

The previous prime is 78421171043. The next prime is 78421171067. The reversal of 78421171065 is 56017112487.

It is not a de Polignac number, because 78421171065 - 2⁶ = 78421171001 is a prime.

It is a super-2 number, since 2×78421171065² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78421171067) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 354591 + ... + 531579.

It is an arithmetic number, because the mean of its divisors is an integer number (3971655600).

Almost surely, 2^78421171065 is an apocalyptic number.

It is an amenable number.

78421171065 is a deficient number, since it is larger than the sum of its proper divisors (48671808135).

78421171065 is a wasteful number, since it uses less digits than its factorization.

78421171065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177377.

The product of its (nonzero) digits is 94080, while the sum is 42.

The spelling of 78421171065 in words is "seventy-eight billion, four hundred twenty-one million, one hundred seventy-one thousand, sixty-five".