813955399 has 4 divisors (see below), whose sum is σ = 815945920. Its totient is φ = 811964880.

The previous prime is 813955379. The next prime is 813955403. The reversal of 813955399 is 993559318.

It is a happy number.

813955399 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 813955399 - 2⁵ = 813955367 is a prime.

It is a super-2 number, since 2×813955399² = 1325046783122498402, which 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 (813955379) 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, 994647 + ... + 995464.

It is an arithmetic number, because the mean of its divisors is an integer number (203986480).

Almost surely, 2^813955399 is an apocalyptic number.

813955399 is a deficient number, since it is larger than the sum of its proper divisors (1990521).

813955399 is a wasteful number, since it uses less digits than its factorization.

813955399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1990520.

The product of its digits is 1312200, while the sum is 52.

The square root of 813955399 is about 28529.9035925465. The cubic root of 813955399 is about 933.6846151201.

The spelling of 813955399 in words is "eight hundred thirteen million, nine hundred fifty-five thousand, three hundred ninety-nine".