45489721 has 4 divisors (see below), whose sum is σ = 45504000. Its totient is φ = 45475444.

The previous prime is 45489709. The next prime is 45489737. The reversal of 45489721 is 12798454.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 45489721 - 2²⁵ = 11935289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (45481721) 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, 60 + ... + 9538.

It is an arithmetic number, because the mean of its divisors is an integer number (11376000).

Almost surely, 2^45489721 is an apocalyptic number.

It is an amenable number.

45489721 is a deficient number, since it is larger than the sum of its proper divisors (14279).

45489721 is an equidigital number, since it uses as much as digits as its factorization.

45489721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14278.

The product of its digits is 80640, while the sum is 40.

The square root of 45489721 is about 6744.6068084063. The cubic root of 45489721 is about 356.9749633937.

The spelling of 45489721 in words is "forty-five million, four hundred eighty-nine thousand, seven hundred twenty-one".