45631721 has 16 divisors (see below), whose sum is σ = 48806400. Its totient is φ = 42595200.

The previous prime is 45631717. The next prime is 45631739. The reversal of 45631721 is 12713654.

It is a cyclic number.

It is not a de Polignac number, because 45631721 - 2² = 45631717 is a prime.

It is a super-2 number, since 2×45631721² = 4164507922843682, which contains 22 as substring.

Its product of digits (5040) is a multiple of the sum of its prime divisors (560).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (45631741) 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, 111365 + ... + 111773.

It is an arithmetic number, because the mean of its divisors is an integer number (3050400).

Almost surely, 2^45631721 is an apocalyptic number.

It is an amenable number.

45631721 is a deficient number, since it is larger than the sum of its proper divisors (3174679).

45631721 is a wasteful number, since it uses less digits than its factorization.

45631721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 560.

The product of its digits is 5040, while the sum is 29.

The square root of 45631721 is about 6755.1255354730. The cubic root of 45631721 is about 357.3460200495.

The spelling of 45631721 in words is "forty-five million, six hundred thirty-one thousand, seven hundred twenty-one".