45581721 has 4 divisors (see below), whose sum is σ = 60775632. Its totient is φ = 30387812.

The previous prime is 45581713. The next prime is 45581737. The reversal of 45581721 is 12718554.

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.

It is a cyclic number.

It is not a de Polignac number, because 45581721 - 2³ = 45581713 is a prime.

It is not an unprimeable number, because it can be changed into a prime (45581771) 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, 7596951 + ... + 7596956.

It is an arithmetic number, because the mean of its divisors is an integer number (15193908).

Almost surely, 2^45581721 is an apocalyptic number.

It is an amenable number.

45581721 is a deficient number, since it is larger than the sum of its proper divisors (15193911).

45581721 is a wasteful number, since it uses less digits than its factorization.

45581721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15193910.

The product of its digits is 11200, while the sum is 33.

The square root of 45581721 is about 6751.4236276507. The cubic root of 45581721 is about 357.2154542173.

The spelling of 45581721 in words is "forty-five million, five hundred eighty-one thousand, seven hundred twenty-one".