812257381 has 24 divisors (see below), whose sum is σ = 916419840. Its totient is φ = 715534560.

The previous prime is 812257373. The next prime is 812257403. The reversal of 812257381 is 183752218.

It is not a de Polignac number, because 812257381 - 2³ = 812257373 is a prime.

It is a super-2 number, since 2×812257381² = 1319524105977958322, which contains 22 as substring.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 812257381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (812257301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 986536 + ... + 987358.

It is an arithmetic number, because the mean of its divisors is an integer number (38184160).

Almost surely, 2^812257381 is an apocalyptic number.

It is an amenable number.

812257381 is a deficient number, since it is larger than the sum of its proper divisors (104162459).

812257381 is a wasteful number, since it uses less digits than its factorization.

812257381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 977 (or 946 counting only the distinct ones).

The product of its digits is 26880, while the sum is 37.

The square root of 812257381 is about 28500.1294909339. The cubic root of 812257381 is about 933.0349001503.

The spelling of 812257381 in words is "eight hundred twelve million, two hundred fifty-seven thousand, three hundred eighty-one".