256797797653 has 4 divisors (see below), whose sum is σ = 257559809260. Its totient is φ = 256035786048.

The previous prime is 256797797591. The next prime is 256797797731. The reversal of 256797797653 is 356797797652.

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 179116861284 + 77680936369 = 423222^2 + 278713^2 .

It is a cyclic number.

It is not a de Polignac number, because 256797797653 - 2¹³ = 256797789461 is a prime.

It is a super-2 number, since 2×256797797653² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256797797153) 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, 381005298 + ... + 381005971.

It is an arithmetic number, because the mean of its divisors is an integer number (64389952315).

Almost surely, 2^256797797653 is an apocalyptic number.

It is an amenable number.

256797797653 is a deficient number, since it is larger than the sum of its proper divisors (762011607).

256797797653 is an equidigital number, since it uses as much as digits as its factorization.

256797797653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 762011606.

The product of its digits is 1050197400, while the sum is 73.

Subtracting 256797797653 from its reverse (356797797652), we obtain a palindrome (99999999999).

The spelling of 256797797653 in words is "two hundred fifty-six billion, seven hundred ninety-seven million, seven hundred ninety-seven thousand, six hundred fifty-three".