78251988 has 12 divisors (see below), whose sum is σ = 182588000. Its totient is φ = 26083992.

The previous prime is 78251983. The next prime is 78252001. The reversal of 78251988 is 88915287.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×78251988² = 12246747251904288, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78251983) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3260488 + ... + 3260511.

Almost surely, 2^78251988 is an apocalyptic number.

It is an amenable number.

78251988 is an abundant number, since it is smaller than the sum of its proper divisors (104336012).

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

78251988 is a wasteful number, since it uses less digits than its factorization.

78251988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6521006 (or 6521004 counting only the distinct ones).

The product of its digits is 322560, while the sum is 48.

The square root of 78251988 is about 8846.0153741671. The cubic root of 78251988 is about 427.7254841394.

The spelling of 78251988 in words is "seventy-eight million, two hundred fifty-one thousand, nine hundred eighty-eight".