813121015 has 16 divisors (see below), whose sum is σ = 1119488832. Its totient is φ = 555393024.

The previous prime is 813120983. The next prime is 813121069. The reversal of 813121015 is 510121318.

It is a cyclic number.

It is not a de Polignac number, because 813121015 - 2⁵ = 813120983 is a prime.

It is a super-2 number, since 2×813121015² = 1322331570069260450, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36204 + ... + 54193.

It is an arithmetic number, because the mean of its divisors is an integer number (69968052).

Almost surely, 2^813121015 is an apocalyptic number.

813121015 is a deficient number, since it is larger than the sum of its proper divisors (306367817).

813121015 is a wasteful number, since it uses less digits than its factorization.

813121015 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90666.

The product of its (nonzero) digits is 240, while the sum is 22.

The square root of 813121015 is about 28515.2768704777. The cubic root of 813121015 is about 933.3654666516.

The spelling of 813121015 in words is "eight hundred thirteen million, one hundred twenty-one thousand, fifteen".