78398131 has 8 divisors (see below), whose sum is σ = 90825824. Its totient is φ = 66277440.

The previous prime is 78398087. The next prime is 78398137. The reversal of 78398131 is 13189387.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 78398131 - 2⁹ = 78397619 is a prime.

It is a super-2 number, since 2×78398131² = 12292533888586322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78398137) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76200 + ... + 77221.

It is an arithmetic number, because the mean of its divisors is an integer number (11353228).

Almost surely, 2^78398131 is an apocalyptic number.

78398131 is a deficient number, since it is larger than the sum of its proper divisors (12427693).

78398131 is a wasteful number, since it uses less digits than its factorization.

78398131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153501.

The product of its digits is 36288, while the sum is 40.

The square root of 78398131 is about 8854.2719068255. The cubic root of 78398131 is about 427.9915911674.

The spelling of 78398131 in words is "seventy-eight million, three hundred ninety-eight thousand, one hundred thirty-one".