801994181 has 2 divisors, whose sum is σ = 801994182. Its totient is φ = 801994180.

The previous prime is 801994163. The next prime is 801994187. The reversal of 801994181 is 181499108.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 529414081 + 272580100 = 23009^2 + 16510^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-801994181 is a prime.

It is a super-2 number, since 2×801994181² = 1286389332715721522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (801994187) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 400997090 + 400997091.

It is an arithmetic number, because the mean of its divisors is an integer number (400997091).

Almost surely, 2^801994181 is an apocalyptic number.

It is an amenable number.

801994181 is a deficient number, since it is larger than the sum of its proper divisors (1).

801994181 is an equidigital number, since it uses as much as digits as its factorization.

801994181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20736, while the sum is 41.

The square root of 801994181 is about 28319.5017788096. The cubic root of 801994181 is about 929.0884740445.

The spelling of 801994181 in words is "eight hundred one million, nine hundred ninety-four thousand, one hundred eighty-one".