78478631 has 16 divisors (see below), whose sum is σ = 98039808. Its totient is φ = 61029600.

The previous prime is 78478627. The next prime is 78478649. The reversal of 78478631 is 13687487.

It is a cyclic number.

It is not a de Polignac number, because 78478631 - 2² = 78478627 is a prime.

It is a super-2 number, since 2×78478631² = 12317791047268322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78478601) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 65861 + ... + 67041.

It is an arithmetic number, because the mean of its divisors is an integer number (6127488).

Almost surely, 2^78478631 is an apocalyptic number.

78478631 is a deficient number, since it is larger than the sum of its proper divisors (19561177).

78478631 is a wasteful number, since it uses less digits than its factorization.

78478631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2062.

The product of its digits is 225792, while the sum is 44.

The square root of 78478631 is about 8858.8165688200. The cubic root of 78478631 is about 428.1380297667.

The spelling of 78478631 in words is "seventy-eight million, four hundred seventy-eight thousand, six hundred thirty-one".