812091387 has 32 divisors (see below), whose sum is σ = 1136540160. Its totient is φ = 515290880.

The previous prime is 812091307. The next prime is 812091419. The reversal of 812091387 is 783190218.

It is a cyclic number.

It is not a de Polignac number, because 812091387 - 2¹¹ = 812089339 is a prime.

It is not an unprimeable number, because it can be changed into a prime (812091307) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2261914 + ... + 2262272.

It is an arithmetic number, because the mean of its divisors is an integer number (35516880).

Almost surely, 2^812091387 is an apocalyptic number.

812091387 is a deficient number, since it is larger than the sum of its proper divisors (324448773).

812091387 is a wasteful number, since it uses less digits than its factorization.

812091387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 803.

The product of its (nonzero) digits is 24192, while the sum is 39.

The square root of 812091387 is about 28497.2171799283. The cubic root of 812091387 is about 932.9713370686.

The spelling of 812091387 in words is "eight hundred twelve million, ninety-one thousand, three hundred eighty-seven".