401561191 has 2 divisors, whose sum is σ = 401561192. Its totient is φ = 401561190.

The previous prime is 401561183. The next prime is 401561201. The reversal of 401561191 is 191165104.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 401561191 - 2³ = 401561183 is a prime.

It is a super-2 number, since 2×401561191² = 322502780234676962, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (401561141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200780595 + 200780596.

It is an arithmetic number, because the mean of its divisors is an integer number (200780596).

Almost surely, 2^401561191 is an apocalyptic number.

401561191 is a deficient number, since it is larger than the sum of its proper divisors (1).

401561191 is an equidigital number, since it uses as much as digits as its factorization.

401561191 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1080, while the sum is 28.

The square root of 401561191 is about 20038.9917660545. The cubic root of 401561191 is about 737.7636347904.

The spelling of 401561191 in words is "four hundred one million, five hundred sixty-one thousand, one hundred ninety-one".