45232721 has 4 divisors (see below), whose sum is σ = 46792500. Its totient is φ = 43672944.

The previous prime is 45232687. The next prime is 45232729. The reversal of 45232721 is 12723254.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12723254 = 2 ⋅6361627.

It can be written as a sum of positive squares in 2 ways, for example, as 19018321 + 26214400 = 4361^2 + 5120^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-45232721 is a prime.

It is a super-4 number, since 4×45232721⁴ (a number of 32 digits) contains 4444 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (45232729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 779846 + ... + 779903.

It is an arithmetic number, because the mean of its divisors is an integer number (11698125).

Almost surely, 2^45232721 is an apocalyptic number.

It is an amenable number.

45232721 is a deficient number, since it is larger than the sum of its proper divisors (1559779).

45232721 is a wasteful number, since it uses less digits than its factorization.

45232721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1559778.

The product of its digits is 3360, while the sum is 26.

The square root of 45232721 is about 6725.5275629500. The cubic root of 45232721 is about 356.3014348225.

Adding to 45232721 its reverse (12723254), we get a palindrome (57955975).

The spelling of 45232721 in words is "forty-five million, two hundred thirty-two thousand, seven hundred twenty-one".