812440631 has 2 divisors, whose sum is σ = 812440632. Its totient is φ = 812440630.

The previous prime is 812440567. The next prime is 812440633. The reversal of 812440631 is 136044218.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 812440631 - 2⁶ = 812440567 is a prime.

It is a super-2 number, since 2×812440631² = 1320119557799356322, which contains 22 as substring.

Together with 812440633, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 812440594 and 812440603.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (812440633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 406220315 + 406220316.

It is an arithmetic number, because the mean of its divisors is an integer number (406220316).

Almost surely, 2^812440631 is an apocalyptic number.

812440631 is a deficient number, since it is larger than the sum of its proper divisors (1).

812440631 is an equidigital number, since it uses as much as digits as its factorization.

812440631 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 812440631 is about 28503.3442073031. The cubic root of 812440631 is about 933.1050609118.

Adding to 812440631 its reverse (136044218), we get a palindrome (948484849).

The spelling of 812440631 in words is "eight hundred twelve million, four hundred forty thousand, six hundred thirty-one".