161423491 has 2 divisors, whose sum is σ = 161423492. Its totient is φ = 161423490.

The previous prime is 161423473. The next prime is 161423527. The reversal of 161423491 is 194324161.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161423491 is a prime.

It is not a weakly prime, because it can be changed into another prime (161423461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80711745 + 80711746.

It is an arithmetic number, because the mean of its divisors is an integer number (80711746).

Almost surely, 2^161423491 is an apocalyptic number.

161423491 is a deficient number, since it is larger than the sum of its proper divisors (1).

161423491 is an equidigital number, since it uses as much as digits as its factorization.

161423491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5184, while the sum is 31.

The square root of 161423491 is about 12705.2544641971. The cubic root of 161423491 is about 544.4887509857.

The spelling of 161423491 in words is "one hundred sixty-one million, four hundred twenty-three thousand, four hundred ninety-one".