813969 has 20 divisors (see below), whose sum is σ = 1311156. Its totient is φ = 500256.

The previous prime is 813961. The next prime is 813971. The reversal of 813969 is 969318.

813969 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 82944 + 731025 = 288^2 + 855^2 .

It is not a de Polignac number, because 813969 - 2³ = 813961 is a prime.

It is a super-2 number, since 2×813969² = 1325091065922, which contains 22 as substring.

It is a plaindrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (813961) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 667 + ... + 1439.

2⁸¹³⁹⁶⁹ is an apocalyptic number.

It is an amenable number.

813969 is a deficient number, since it is larger than the sum of its proper divisors (497187).

813969 is a wasteful number, since it uses less digits than its factorization.

813969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 798 (or 789 counting only the distinct ones).

The product of its digits is 11664, while the sum is 36.

The square root of 813969 is about 902.2023054726. The cubic root of 813969 is about 93.3689815640.

It can be divided in two parts, 81 and 3969, that multiplied together give a square (321489 = 567²).

The spelling of 813969 in words is "eight hundred thirteen thousand, nine hundred sixty-nine".