78861965 has 32 divisors (see below), whose sum is σ = 117040896. Its totient is φ = 49674240.

The previous prime is 78861961. The next prime is 78862001. The reversal of 78861965 is 56916887.

It is a happy number.

It is not a de Polignac number, because 78861965 - 2² = 78861961 is a prime.

It is a super-2 number, since 2×78861965² = 12438419047322450, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78861961) 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, 160370 + ... + 160860.

It is an arithmetic number, because the mean of its divisors is an integer number (3657528).

Almost surely, 2^78861965 is an apocalyptic number.

It is an amenable number.

78861965 is a deficient number, since it is larger than the sum of its proper divisors (38178931).

78861965 is a wasteful number, since it uses less digits than its factorization.

78861965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 869.

The product of its digits is 725760, while the sum is 50.

The square root of 78861965 is about 8880.4259469915. The cubic root of 78861965 is about 428.8339872357.

The spelling of 78861965 in words is "seventy-eight million, eight hundred sixty-one thousand, nine hundred sixty-five".