161561326 has 16 divisors (see below), whose sum is σ = 247539600. Its totient is φ = 79066368.

The previous prime is 161561303. The next prime is 161561327. The reversal of 161561326 is 623165161.

It is a super-2 number, since 2×161561326² = 52204124117756552, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161561327) 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, 13630 + ... + 22558.

It is an arithmetic number, because the mean of its divisors is an integer number (15471225).

Almost surely, 2^161561326 is an apocalyptic number.

161561326 is a deficient number, since it is larger than the sum of its proper divisors (85978274).

161561326 is a wasteful number, since it uses less digits than its factorization.

161561326 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9123.

The product of its digits is 6480, while the sum is 31.

The square root of 161561326 is about 12710.6776373252. The cubic root of 161561326 is about 544.6436814644.

The spelling of 161561326 in words is "one hundred sixty-one million, five hundred sixty-one thousand, three hundred twenty-six".