801981161 has 2 divisors, whose sum is σ = 801981162. Its totient is φ = 801981160.

The previous prime is 801981151. The next prime is 801981247. The reversal of 801981161 is 161189108.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 780867136 + 21114025 = 27944^2 + 4595^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-801981161 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (801981101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 400990580 + 400990581.

It is an arithmetic number, because the mean of its divisors is an integer number (400990581).

Almost surely, 2^801981161 is an apocalyptic number.

It is an amenable number.

801981161 is a deficient number, since it is larger than the sum of its proper divisors (1).

801981161 is an equidigital number, since it uses as much as digits as its factorization.

801981161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 35.

The square root of 801981161 is about 28319.2719009511. The cubic root of 801981161 is about 929.0834462452.

The spelling of 801981161 in words is "eight hundred one million, nine hundred eighty-one thousand, one hundred sixty-one".