813961 has 2 divisors, whose sum is σ = 813962. Its totient is φ = 813960.

The previous prime is 813931. The next prime is 813971. The reversal of 813961 is 169318.

It is a happy number.

813961 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 732736 + 81225 = 856^2 + 285^2 .

It is a cyclic number.

It is not a de Polignac number, because 813961 - 2⁷ = 813833 is a prime.

813961 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (813931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 406980 + 406981.

It is an arithmetic number, because the mean of its divisors is an integer number (406981).

2⁸¹³⁹⁶¹ is an apocalyptic number.

It is an amenable number.

813961 is a deficient number, since it is larger than the sum of its proper divisors (1).

813961 is an equidigital number, since it uses as much as digits as its factorization.

813961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1296, while the sum is 28.

The square root of 813961 is about 902.1978718663. The cubic root of 813961 is about 93.3686756743.

The spelling of 813961 in words is "eight hundred thirteen thousand, nine hundred sixty-one".