78111872 has 32 divisors (see below), whose sum is σ = 164771820. Its totient is φ = 36757504.

The previous prime is 78111863. The next prime is 78111899. The reversal of 78111872 is 27811187.

It can be written as a sum of positive squares in 2 ways, for example, as 73685056 + 4426816 = 8584^2 + 2104^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is a super-2 number, since 2×78111872² = 12202929094688768, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15773 + ... + 20124.

Almost surely, 2^78111872 is an apocalyptic number.

It is an amenable number.

78111872 is an abundant number, since it is smaller than the sum of its proper divisors (86659948).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78111872 is a wasteful number, since it uses less digits than its factorization.

78111872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35928 (or 35916 counting only the distinct ones).

The product of its digits is 6272, while the sum is 35.

The square root of 78111872 is about 8838.0921018057. The cubic root of 78111872 is about 427.4700401926.

The spelling of 78111872 in words is "seventy-eight million, one hundred eleven thousand, eight hundred seventy-two".