56221520 has 40 divisors (see below), whose sum is σ = 132003456. Its totient is φ = 22267008.

The previous prime is 56221519. The next prime is 56221531. The reversal of 56221520 is 2512265.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×56221520² = 6321718622220800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4829 + ... + 11651.

Almost surely, 2^56221520 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 56221520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (66001728).

56221520 is an abundant number, since it is smaller than the sum of its proper divisors (75781936).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

56221520 is a wasteful number, since it uses less digits than its factorization.

56221520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6939 (or 6933 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 56221520 is about 7498.1010929435. The cubic root of 56221520 is about 383.0900401168.

Adding to 56221520 its reverse (2512265), we get a palindrome (58733785).

The spelling of 56221520 in words is "fifty-six million, two hundred twenty-one thousand, five hundred twenty".