56221521 has 8 divisors (see below), whose sum is σ = 75003264. Its totient is φ = 37460400.

The previous prime is 56221519. The next prime is 56221531. The reversal of 56221521 is 12512265.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 56221521 - 2¹ = 56221519 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 56221491 and 56221500.

It is not an unprimeable number, because it can be changed into a prime (56221531) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3096 + ... + 11046.

It is an arithmetic number, because the mean of its divisors is an integer number (9375408).

Almost surely, 2^56221521 is an apocalyptic number.

It is an amenable number.

56221521 is a deficient number, since it is larger than the sum of its proper divisors (18781743).

56221521 is a wasteful number, since it uses less digits than its factorization.

56221521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10311.

The product of its digits is 1200, while the sum is 24.

The square root of 56221521 is about 7498.1011596270. The cubic root of 56221521 is about 383.0900423881.

Adding to 56221521 its reverse (12512265), we get a palindrome (68733786).

The spelling of 56221521 in words is "fifty-six million, two hundred twenty-one thousand, five hundred twenty-one".