811925342761 has 9 divisors (see below), whose sum is σ = 879198114789. Its totient is φ = 749458734336.

The previous prime is 811925342707. The next prime is 811925342783. The reversal of 811925342761 is 167243529118.

It is a happy number.

The square root of 811925342761 is 901069.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 72566123161 + 739359219600 = 269381^2 + 859860^2 .

It is not a de Polignac number, because 811925342761 - 2³⁷ = 674486389289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (811925342561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 11679241 + ... + 11748553.

It is an arithmetic number, because the mean of its divisors is an integer number (97688679421).

Almost surely, 2^811925342761 is an apocalyptic number.

811925342761 is the 901069-th square number.

811925342761 is the 450535-th centered octagonal number.

It is an amenable number.

811925342761 is a deficient number, since it is larger than the sum of its proper divisors (67272772028).

811925342761 is an frugal number, since it uses more digits than its factorization.

811925342761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138652 (or 69326 counting only the distinct ones).

The product of its digits is 725760, while the sum is 49.

Multiplying 811925342761 by its sum of digits (49), we get a square (39784341795289 = 6307483²).

The spelling of 811925342761 in words is "eight hundred eleven billion, nine hundred twenty-five million, three hundred forty-two thousand, seven hundred sixty-one".