78173972 has 12 divisors (see below), whose sum is σ = 139715520. Its totient is φ = 38255256.

The previous prime is 78173947. The next prime is 78174049. The reversal of 78173972 is 27937187.

It is a super-2 number, since 2×78173972² = 12222339796513568, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 207722 + ... + 208097.

It is an arithmetic number, because the mean of its divisors is an integer number (11642960).

Almost surely, 2^78173972 is an apocalyptic number.

It is an amenable number.

78173972 is a deficient number, since it is larger than the sum of its proper divisors (61541548).

78173972 is a wasteful number, since it uses less digits than its factorization.

78173972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 415870 (or 415868 counting only the distinct ones).

The product of its digits is 148176, while the sum is 44.

The square root of 78173972 is about 8841.6046055001. The cubic root of 78173972 is about 427.5832916833.

The spelling of 78173972 in words is "seventy-eight million, one hundred seventy-three thousand, nine hundred seventy-two".