56501221 has 4 divisors (see below), whose sum is σ = 64572832. Its totient is φ = 48429612.

The previous prime is 56501219. The next prime is 56501227. The reversal of 56501221 is 12210565.

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 an emirpimes, since its reverse is a distinct semiprime: 12210565 = 5 ⋅2442113.

It is not a de Polignac number, because 56501221 - 2¹ = 56501219 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 56501192 and 56501201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56501227) 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, 4035795 + ... + 4035808.

It is an arithmetic number, because the mean of its divisors is an integer number (16143208).

Almost surely, 2^56501221 is an apocalyptic number.

It is an amenable number.

56501221 is a deficient number, since it is larger than the sum of its proper divisors (8071611).

56501221 is an equidigital number, since it uses as much as digits as its factorization.

56501221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8071610.

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 56501221 is about 7516.7294084595. The cubic root of 56501221 is about 383.7242780738.

Adding to 56501221 its reverse (12210565), we get a palindrome (68711786).

The spelling of 56501221 in words is "fifty-six million, five hundred one thousand, two hundred twenty-one".