56128237621 has 2 divisors, whose sum is σ = 56128237622. Its totient is φ = 56128237620.

The previous prime is 56128237513. The next prime is 56128237631. The reversal of 56128237621 is 12673282165.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 56062400625 + 65836996 = 236775^2 + 8114^2 .

It is a cyclic number.

It is not a de Polignac number, because 56128237621 - 2¹³ = 56128229429 is a prime.

It is a super-3 number, since 3×56128237621³ (a number of 33 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56128237631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28064118810 + 28064118811.

It is an arithmetic number, because the mean of its divisors is an integer number (28064118811).

Almost surely, 2^56128237621 is an apocalyptic number.

It is an amenable number.

56128237621 is a deficient number, since it is larger than the sum of its proper divisors (1).

56128237621 is an equidigital number, since it uses as much as digits as its factorization.

56128237621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 241920, while the sum is 43.

The spelling of 56128237621 in words is "fifty-six billion, one hundred twenty-eight million, two hundred thirty-seven thousand, six hundred twenty-one".