78019986 has 16 divisors (see below), whose sum is σ = 170225568. Its totient is φ = 23642400.

The previous prime is 78019973. The next prime is 78020009. The reversal of 78019986 is 68991087.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 590995 + ... + 591126.

It is an arithmetic number, because the mean of its divisors is an integer number (10639098).

Almost surely, 2^78019986 is an apocalyptic number.

78019986 is an abundant number, since it is smaller than the sum of its proper divisors (92205582).

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

78019986 is a wasteful number, since it uses less digits than its factorization.

78019986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1182137.

The product of its (nonzero) digits is 217728, while the sum is 48.

The square root of 78019986 is about 8832.8922782971. The cubic root of 78019986 is about 427.3023579407.

The spelling of 78019986 in words is "seventy-eight million, nineteen thousand, nine hundred eighty-six".