194069891 has 2 divisors, whose sum is σ = 194069892. Its totient is φ = 194069890.

The previous prime is 194069861. The next prime is 194069893. The reversal of 194069891 is 198960491.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-194069891 is a prime.

It is a Sophie Germain prime.

Together with 194069893, 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 (194069893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97034945 + 97034946.

It is an arithmetic number, because the mean of its divisors is an integer number (97034946).

Almost surely, 2^194069891 is an apocalyptic number.

194069891 is a deficient number, since it is larger than the sum of its proper divisors (1).

194069891 is an equidigital number, since it uses as much as digits as its factorization.

194069891 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 139968, while the sum is 47.

The square root of 194069891 is about 13930.8969919385. The cubic root of 194069891 is about 578.9655471121.

The spelling of 194069891 in words is "one hundred ninety-four million, sixty-nine thousand, eight hundred ninety-one".