45217921 has 4 divisors (see below), whose sum is σ = 51677632. Its totient is φ = 38758212.

The previous prime is 45217919. The next prime is 45217961. The reversal of 45217921 is 12971254.

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 45217921 - 2¹ = 45217919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (45217961) 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, 3229845 + ... + 3229858.

It is an arithmetic number, because the mean of its divisors is an integer number (12919408).

Almost surely, 2^45217921 is an apocalyptic number.

It is an amenable number.

45217921 is a deficient number, since it is larger than the sum of its proper divisors (6459711).

45217921 is an equidigital number, since it uses as much as digits as its factorization.

45217921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6459710.

The product of its digits is 5040, while the sum is 31.

The square root of 45217921 is about 6724.4271875008. The cubic root of 45217921 is about 356.2625703577.

The spelling of 45217921 in words is "forty-five million, two hundred seventeen thousand, nine hundred twenty-one".