396161891 has 2 divisors, whose sum is σ = 396161892. Its totient is φ = 396161890.

The previous prime is 396161861. The next prime is 396161893. The reversal of 396161891 is 198161693.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 396161891 - 2⁶ = 396161827 is a prime.

It is a Sophie Germain prime.

Together with 396161893, 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 (396161893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 198080945 + 198080946.

It is an arithmetic number, because the mean of its divisors is an integer number (198080946).

Almost surely, 2^396161891 is an apocalyptic number.

396161891 is a deficient number, since it is larger than the sum of its proper divisors (1).

396161891 is an equidigital number, since it uses as much as digits as its factorization.

396161891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 69984, while the sum is 44.

The square root of 396161891 is about 19903.8159909099. The cubic root of 396161891 is about 734.4421027466.

The spelling of 396161891 in words is "three hundred ninety-six million, one hundred sixty-one thousand, eight hundred ninety-one".