813256124869 has 2 divisors, whose sum is σ = 813256124870. Its totient is φ = 813256124868.

The previous prime is 813256124861. The next prime is 813256124897. The reversal of 813256124869 is 968421652318.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 408880955844 + 404375169025 = 639438^2 + 635905^2 .

It is a cyclic number.

It is not a de Polignac number, because 813256124869 - 2³ = 813256124861 is a prime.

It is a super-2 number, since 2×813256124869² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (813256124861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 406628062434 + 406628062435.

It is an arithmetic number, because the mean of its divisors is an integer number (406628062435).

Almost surely, 2^813256124869 is an apocalyptic number.

It is an amenable number.

813256124869 is a deficient number, since it is larger than the sum of its proper divisors (1).

813256124869 is an equidigital number, since it uses as much as digits as its factorization.

813256124869 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4976640, while the sum is 55.

The spelling of 813256124869 in words is "eight hundred thirteen billion, two hundred fifty-six million, one hundred twenty-four thousand, eight hundred sixty-nine".