815855815279 has 16 divisors (see below), whose sum is σ = 845510814720. Its totient is φ = 786689074080.

The previous prime is 815855815277. The next prime is 815855815303. The reversal of 815855815279 is 972518558518.

It is a cyclic number.

It is not a de Polignac number, because 815855815279 - 2¹ = 815855815277 is a prime.

It is a super-2 number, since 2×815855815279² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 815855815279.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (815855815277) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38874969 + ... + 38895949.

It is an arithmetic number, because the mean of its divisors is an integer number (52844425920).

Almost surely, 2^815855815279 is an apocalyptic number.

815855815279 is a deficient number, since it is larger than the sum of its proper divisors (29654999441).

815855815279 is a wasteful number, since it uses less digits than its factorization.

815855815279 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32550.

The product of its digits is 40320000, while the sum is 64.

The spelling of 815855815279 in words is "eight hundred fifteen billion, eight hundred fifty-five million, eight hundred fifteen thousand, two hundred seventy-nine".