78191288 has 16 divisors (see below), whose sum is σ = 167552880. Its totient is φ = 33510528.

The previous prime is 78191257. The next prime is 78191291. The reversal of 78191288 is 88219187.

It is a super-2 number, since 2×78191288² = 12227755038197888, which contains 22 as substring.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is a nialpdrome in base 14.

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, 698081 + ... + 698192.

It is an arithmetic number, because the mean of its divisors is an integer number (10472055).

Almost surely, 2^78191288 is an apocalyptic number.

It is an amenable number.

78191288 is an abundant number, since it is smaller than the sum of its proper divisors (89361592).

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

78191288 is a wasteful number, since it uses less digits than its factorization.

78191288 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1396286 (or 1396282 counting only the distinct ones).

The product of its digits is 64512, while the sum is 44.

The square root of 78191288 is about 8842.5837852971. The cubic root of 78191288 is about 427.6148601004.

The spelling of 78191288 in words is "seventy-eight million, one hundred ninety-one thousand, two hundred eighty-eight".