812784881 has 2 divisors, whose sum is σ = 812784882. Its totient is φ = 812784880.

The previous prime is 812784857. The next prime is 812784911. The reversal of 812784881 is 188487218.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 794337856 + 18447025 = 28184^2 + 4295^2 .

It is a cyclic number.

It is not a de Polignac number, because 812784881 - 2¹⁰ = 812783857 is a prime.

It is a super-2 number, since 2×812784881² = 1321238525564368322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (812784781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 406392440 + 406392441.

It is an arithmetic number, because the mean of its divisors is an integer number (406392441).

Almost surely, 2^812784881 is an apocalyptic number.

It is an amenable number.

812784881 is a deficient number, since it is larger than the sum of its proper divisors (1).

812784881 is an equidigital number, since it uses as much as digits as its factorization.

812784881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 229376, while the sum is 47.

The square root of 812784881 is about 28509.3823328391. The cubic root of 812784881 is about 933.2368350771.

The spelling of 812784881 in words is "eight hundred twelve million, seven hundred eighty-four thousand, eight hundred eighty-one".