56121520 has 120 divisors (see below), whose sum is σ = 161748576. Its totient is φ = 17731584.

The previous prime is 56121511. The next prime is 56121523. The reversal of 56121520 is 2512165.

It is a super-2 number, since 2×56121520² = 6299250014220800, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 56121491 and 56121500.

It is not an unprimeable number, because it can be changed into a prime (56121523) 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 23 ways as a sum of consecutive naturals, for example, 94344 + ... + 94936.

Almost surely, 2^56121520 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 56121520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80874288).

56121520 is an abundant number, since it is smaller than the sum of its proper divisors (105627056).

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

56121520 is a wasteful number, since it uses less digits than its factorization.

56121520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 639 (or 620 counting only the distinct ones).

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

The square root of 56121520 is about 7491.4297700773. The cubic root of 56121520 is about 382.8627739999.

Adding to 56121520 its reverse (2512165), we get a palindrome (58633685).

The spelling of 56121520 in words is "fifty-six million, one hundred twenty-one thousand, five hundred twenty".