2156631 has 8 divisors (see below), whose sum is σ = 2889984. Its totient is φ = 1430520.

The previous prime is 2156629. The next prime is 2156647. The reversal of 2156631 is 1366512.

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

It is not a de Polignac number, because 2156631 - 2¹ = 2156629 is a prime.

It is a super-2 number, since 2×2156631² = 9302114540322, which contains 22 as substring.

2156631 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2156681) 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, 1071 + ... + 2336.

It is an arithmetic number, because the mean of its divisors is an integer number (361248).

2^2156631 is an apocalyptic number.

2156631 is a deficient number, since it is larger than the sum of its proper divisors (733353).

2156631 is a wasteful number, since it uses less digits than its factorization.

2156631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3621.

The product of its digits is 1080, while the sum is 24.

The square root of 2156631 is about 1468.5472413239. The cubic root of 2156631 is about 129.1988400373.

The spelling of 2156631 in words is "two million, one hundred fifty-six thousand, six hundred thirty-one".