161319291 has 16 divisors (see below), whose sum is σ = 258758400. Its totient is φ = 87330528.

The previous prime is 161319287. The next prime is 161319293. The reversal of 161319291 is 192913161.

It is not a de Polignac number, because 161319291 - 2² = 161319287 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161319293) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 201756 + ... + 202553.

It is an arithmetic number, because the mean of its divisors is an integer number (16172400).

Almost surely, 2^161319291 is an apocalyptic number.

161319291 is a deficient number, since it is larger than the sum of its proper divisors (97439109).

161319291 is a wasteful number, since it uses less digits than its factorization.

161319291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 404338.

The product of its digits is 2916, while the sum is 33.

The square root of 161319291 is about 12701.1531366250. The cubic root of 161319291 is about 544.3715686606.

The spelling of 161319291 in words is "one hundred sixty-one million, three hundred nineteen thousand, two hundred ninety-one".