161661610 has 32 divisors (see below), whose sum is σ = 320609664. Its totient is φ = 58200000.

The previous prime is 161661589. The next prime is 161661613. The reversal of 161661610 is 16166161.

It is a super-2 number, since 2×161661610² = 52268952295584200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161661613) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3835 + ... + 18385.

It is an arithmetic number, because the mean of its divisors is an integer number (10019052).

Almost surely, 2^161661610 is an apocalyptic number.

161661610 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161661610 is a deficient number, since it is larger than the sum of its proper divisors (158948054).

161661610 is a wasteful number, since it uses less digits than its factorization.

161661610 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14670.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 161661610 is about 12714.6218976421. The cubic root of 161661610 is about 544.7563481758.

The spelling of 161661610 in words is "one hundred sixty-one million, six hundred sixty-one thousand, six hundred ten".