78877631 has 16 divisors (see below), whose sum is σ = 92110080. Its totient is φ = 66147840.

The previous prime is 78877573. The next prime is 78877633. The reversal of 78877631 is 13677887.

It is a cyclic number.

It is not a de Polignac number, because 78877631 - 2⁶ = 78877567 is a prime.

It is a super-2 number, since 2×78877631² = 12443361344344322, which contains 22 as substring.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78877633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 136415 + ... + 136991.

It is an arithmetic number, because the mean of its divisors is an integer number (5756880).

Almost surely, 2^78877631 is an apocalyptic number.

78877631 is a deficient number, since it is larger than the sum of its proper divisors (13232449).

78877631 is a wasteful number, since it uses less digits than its factorization.

78877631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 974.

The product of its digits is 395136, while the sum is 47.

The square root of 78877631 is about 8881.3079554759. The cubic root of 78877631 is about 428.8623814409.

The spelling of 78877631 in words is "seventy-eight million, eight hundred seventy-seven thousand, six hundred thirty-one".