161121010091 has 2 divisors, whose sum is σ = 161121010092. Its totient is φ = 161121010090.

The previous prime is 161121010033. The next prime is 161121010159. The reversal of 161121010091 is 190010121161.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 161121010091 - 2⁶ = 161121010027 is a prime.

It is not a weakly prime, because it can be changed into another prime (161121013091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80560505045 + 80560505046.

It is an arithmetic number, because the mean of its divisors is an integer number (80560505046).

Almost surely, 2^161121010091 is an apocalyptic number.

161121010091 is a deficient number, since it is larger than the sum of its proper divisors (1).

161121010091 is an equidigital number, since it uses as much as digits as its factorization.

161121010091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108, while the sum is 23.

The spelling of 161121010091 in words is "one hundred sixty-one billion, one hundred twenty-one million, ten thousand, ninety-one".