2251561631 has 16 divisors (see below), whose sum is σ = 2470048128. Its totient is φ = 2035413600.

The previous prime is 2251561619. The next prime is 2251561643. The reversal of 2251561631 is 1361651522.

It is an interprime number because it is at equal distance from previous prime (2251561619) and next prime (2251561643).

It is not a de Polignac number, because 2251561631 - 2³⁰ = 1177819807 is a prime.

It is a super-2 number, since 2×2251561631² = 10139059556382760322, 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 (2251561601) 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, 2377100 + ... + 2378046.

It is an arithmetic number, because the mean of its divisors is an integer number (154378008).

Almost surely, 2^2251561631 is an apocalyptic number.

2251561631 is a deficient number, since it is larger than the sum of its proper divisors (218486497).

2251561631 is a wasteful number, since it uses less digits than its factorization.

2251561631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1942.

The product of its digits is 10800, while the sum is 32.

The square root of 2251561631 is about 47450.6230833695. The cubic root of 2251561631 is about 1310.6737848472.

The spelling of 2251561631 in words is "two billion, two hundred fifty-one million, five hundred sixty-one thousand, six hundred thirty-one".