161583197 has 4 divisors (see below), whose sum is σ = 161647740. Its totient is φ = 161518656.

The previous prime is 161583179. The next prime is 161583251. The reversal of 161583197 is 791385161.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 74459641 + 87123556 = 8629^2 + 9334^2 .

It is a cyclic number.

It is not a de Polignac number, because 161583197 - 2²² = 157388893 is a prime.

It is a super-2 number, since 2×161583197² = 52218259105481618, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161583397) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28358 + ... + 33575.

It is an arithmetic number, because the mean of its divisors is an integer number (40411935).

Almost surely, 2^161583197 is an apocalyptic number.

It is an amenable number.

161583197 is a deficient number, since it is larger than the sum of its proper divisors (64543).

161583197 is an equidigital number, since it uses as much as digits as its factorization.

161583197 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64542.

The product of its digits is 45360, while the sum is 41.

The square root of 161583197 is about 12711.5379478645. The cubic root of 161583197 is about 544.6682569920.

The spelling of 161583197 in words is "one hundred sixty-one million, five hundred eighty-three thousand, one hundred ninety-seven".