811977601 has 2 divisors, whose sum is σ = 811977602. Its totient is φ = 811977600.

The previous prime is 811977599. The next prime is 811977667. The reversal of 811977601 is 106779118.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 576048001 + 235929600 = 24001^2 + 15360^2 .

It is a cyclic number.

It is not a de Polignac number, because 811977601 - 2¹ = 811977599 is a prime.

Together with 811977599, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (811977701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 405988800 + 405988801.

It is an arithmetic number, because the mean of its divisors is an integer number (405988801).

Almost surely, 2^811977601 is an apocalyptic number.

It is an amenable number.

811977601 is a deficient number, since it is larger than the sum of its proper divisors (1).

811977601 is an equidigital number, since it uses as much as digits as its factorization.

811977601 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21168, while the sum is 40.

The square root of 811977601 is about 28495.2206694386. The cubic root of 811977601 is about 932.9277606777.

The spelling of 811977601 in words is "eight hundred eleven million, nine hundred seventy-seven thousand, six hundred one".