161581122 has 16 divisors (see below), whose sum is σ = 359069280. Its totient is φ = 53860356.

The previous prime is 161581087. The next prime is 161581129. The reversal of 161581122 is 221185161.

161581122 is a `hidden beast` number, since 1 + 61 + 581 + 1 + 22 = 666.

It is a super-2 number, since 2×161581122² = 52216917973557768, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (161581129) 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, 1496068 + ... + 1496175.

It is an arithmetic number, because the mean of its divisors is an integer number (22441830).

Almost surely, 2^161581122 is an apocalyptic number.

161581122 is an abundant number, since it is smaller than the sum of its proper divisors (197488158).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161581122 is a wasteful number, since it uses less digits than its factorization.

161581122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2992254 (or 2992248 counting only the distinct ones).

The product of its digits is 960, while the sum is 27.

The square root of 161581122 is about 12711.4563288397. The cubic root of 161581122 is about 544.6659254966.

The spelling of 161581122 in words is "one hundred sixty-one million, five hundred eighty-one thousand, one hundred twenty-two".