78365128 has 8 divisors (see below), whose sum is σ = 146934630. Its totient is φ = 39182560.

The previous prime is 78365107. The next prime is 78365159. The reversal of 78365128 is 82156387.

It can be written as a sum of positive squares in only one way, i.e., 46758244 + 31606884 = 6838^2 + 5622^2 .

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

It is a super-2 number, since 2×78365128² = 12282186572912768, 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, 4897813 + ... + 4897828.

Almost surely, 2^78365128 is an apocalyptic number.

It is an amenable number.

78365128 is a deficient number, since it is larger than the sum of its proper divisors (68569502).

78365128 is a wasteful number, since it uses less digits than its factorization.

78365128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9795647 (or 9795643 counting only the distinct ones).

The product of its digits is 80640, while the sum is 40.

The square root of 78365128 is about 8852.4080339758. The cubic root of 78365128 is about 427.9315260067.

The spelling of 78365128 in words is "seventy-eight million, three hundred sixty-five thousand, one hundred twenty-eight".