78879631 has 4 divisors (see below), whose sum is σ = 79830072. Its totient is φ = 77929192.

The previous prime is 78879629. The next prime is 78879667. The reversal of 78879631 is 13697887.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 78879631 - 2¹ = 78879629 is a prime.

It is a super-2 number, since 2×78879631² = 12443992373392322, 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 (78879601) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 475096 + ... + 475261.

It is an arithmetic number, because the mean of its divisors is an integer number (19957518).

Almost surely, 2^78879631 is an apocalyptic number.

78879631 is a deficient number, since it is larger than the sum of its proper divisors (950441).

78879631 is an equidigital number, since it uses as much as digits as its factorization.

78879631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 950440.

The product of its digits is 508032, while the sum is 49.

The square root of 78879631 is about 8881.4205507903. The cubic root of 78879631 is about 428.8660061167.

The spelling of 78879631 in words is "seventy-eight million, eight hundred seventy-nine thousand, six hundred thirty-one".