56000002781 has 4 divisors (see below), whose sum is σ = 56208181500. Its totient is φ = 55791824064.

The previous prime is 56000002777. The next prime is 56000002829. The reversal of 56000002781 is 18720000065.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 28786551556 + 27213451225 = 169666^2 + 164965^2 .

It is a cyclic number.

It is not a de Polignac number, because 56000002781 - 2² = 56000002777 is a prime.

It is a super-2 number, since 2×56000002781² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56000002711) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 104088956 + ... + 104089493.

It is an arithmetic number, because the mean of its divisors is an integer number (14052045375).

Almost surely, 2^56000002781 is an apocalyptic number.

It is an amenable number.

56000002781 is a deficient number, since it is larger than the sum of its proper divisors (208178719).

56000002781 is a wasteful number, since it uses less digits than its factorization.

56000002781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208178718.

The product of its (nonzero) digits is 3360, while the sum is 29.

The spelling of 56000002781 in words is "fifty-six billion, two thousand, seven hundred eighty-one".