56120821 has 2 divisors, whose sum is σ = 56120822. Its totient is φ = 56120820.

The previous prime is 56120807. The next prime is 56120837. The reversal of 56120821 is 12802165.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29484900 + 26635921 = 5430^2 + 5161^2 .

It is a cyclic number.

It is not a de Polignac number, because 56120821 - 2²⁵ = 22566389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56120861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28060410 + 28060411.

It is an arithmetic number, because the mean of its divisors is an integer number (28060411).

Almost surely, 2^56120821 is an apocalyptic number.

It is an amenable number.

56120821 is a deficient number, since it is larger than the sum of its proper divisors (1).

56120821 is an equidigital number, since it uses as much as digits as its factorization.

56120821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 960, while the sum is 25.

The square root of 56120821 is about 7491.3831166214. The cubic root of 56120821 is about 382.8611844599.

Adding to 56120821 its reverse (12802165), we get a palindrome (68922986).

The spelling of 56120821 in words is "fifty-six million, one hundred twenty thousand, eight hundred twenty-one".