161661055 has 16 divisors (see below), whose sum is σ = 197817984. Its totient is φ = 126800640.

The previous prime is 161660999. The next prime is 161661083. The reversal of 161661055 is 550166161.

161661055 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 161661055 - 2²⁷ = 27443327 is a prime.

It is a super-2 number, since 2×161661055² = 52268593407426050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 64842 + ... + 67288.

It is an arithmetic number, because the mean of its divisors is an integer number (12363624).

Almost surely, 2^161661055 is an apocalyptic number.

161661055 is a deficient number, since it is larger than the sum of its proper divisors (36156929).

161661055 is a wasteful number, since it uses less digits than its factorization.

161661055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2706.

The product of its (nonzero) digits is 5400, while the sum is 31.

The square root of 161661055 is about 12714.6000723578. The cubic root of 161661055 is about 544.7557247746.

The spelling of 161661055 in words is "one hundred sixty-one million, six hundred sixty-one thousand, fifty-five".