161913493 has 8 divisors (see below), whose sum is σ = 188820800. Its totient is φ = 138782700.

The previous prime is 161913487. The next prime is 161913503. The reversal of 161913493 is 394319161.

161913493 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a de Polignac number, because none of the positive numbers 2^k-161913493 is a prime.

It is a super-2 number, since 2×161913493² = 52431958430922098, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161913413) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 235683 + ... + 236368.

It is an arithmetic number, because the mean of its divisors is an integer number (23602600).

Almost surely, 2^161913493 is an apocalyptic number.

It is an amenable number.

161913493 is a deficient number, since it is larger than the sum of its proper divisors (26907307).

161913493 is an frugal number, since it uses more digits than its factorization.

161913493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 472072 (or 472058 counting only the distinct ones).

The product of its digits is 17496, while the sum is 37.

The square root of 161913493 is about 12724.5232916601. The cubic root of 161913493 is about 545.0391274548.

The spelling of 161913493 in words is "one hundred sixty-one million, nine hundred thirteen thousand, four hundred ninety-three".