78019992 has 24 divisors (see below), whose sum is σ = 211304340. Its totient is φ = 26006640.

The previous prime is 78019973. The next prime is 78020009. The reversal of 78019992 is 29991087.

It is a tau number, because it is divible by the number of its divisors (24).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 541734 + ... + 541877.

Almost surely, 2^78019992 is an apocalyptic number.

78019992 is a gapful number since it is divisible by the number (72) formed by its first and last digit.

It is an amenable number.

78019992 is an abundant number, since it is smaller than the sum of its proper divisors (133284348).

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

78019992 is a wasteful number, since it uses less digits than its factorization.

78019992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1083623 (or 1083616 counting only the distinct ones).

The product of its (nonzero) digits is 81648, while the sum is 45.

The square root of 78019992 is about 8832.8926179367. The cubic root of 78019992 is about 427.3023688944.

The spelling of 78019992 in words is "seventy-eight million, nineteen thousand, nine hundred ninety-two".