78172804 has 6 divisors (see below), whose sum is σ = 136802414. Its totient is φ = 39086400.

The previous prime is 78172799. The next prime is 78172811. The reversal of 78172804 is 40827187.

It can be written as a sum of positive squares in only one way, i.e., 76737600 + 1435204 = 8760^2 + 1198^2 .

It is a super-2 number, since 2×78172804² = 12221974570444832, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9771597 + ... + 9771604.

Almost surely, 2^78172804 is an apocalyptic number.

It is an amenable number.

78172804 is a deficient number, since it is larger than the sum of its proper divisors (58629610).

78172804 is a wasteful number, since it uses less digits than its factorization.

78172804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19543205 (or 19543203 counting only the distinct ones).

The product of its (nonzero) digits is 25088, while the sum is 37.

The square root of 78172804 is about 8841.5385538943. The cubic root of 78172804 is about 427.5811621605.

The spelling of 78172804 in words is "seventy-eight million, one hundred seventy-two thousand, eight hundred four".