816987877 has 2 divisors, whose sum is σ = 816987878. Its totient is φ = 816987876.

The previous prime is 816987869. The next prime is 816987893. The reversal of 816987877 is 778789618.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 718561636 + 98426241 = 26806^2 + 9921^2 .

It is a cyclic number.

It is not a de Polignac number, because 816987877 - 2³ = 816987869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (816987817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 408493938 + 408493939.

It is an arithmetic number, because the mean of its divisors is an integer number (408493939).

Almost surely, 2^816987877 is an apocalyptic number.

It is an amenable number.

816987877 is a deficient number, since it is larger than the sum of its proper divisors (1).

816987877 is an equidigital number, since it uses as much as digits as its factorization.

816987877 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9483264, while the sum is 61.

The square root of 816987877 is about 28582.9997900850. Note that the first 3 decimals coincide. The cubic root of 816987877 is about 934.8426921338.

The spelling of 816987877 in words is "eight hundred sixteen million, nine hundred eighty-seven thousand, eight hundred seventy-seven".