161656210 has 16 divisors (see below), whose sum is σ = 291528792. Its totient is φ = 64540800.

The previous prime is 161656207. The next prime is 161656267. The reversal of 161656210 is 12656161.

It can be written as a sum of positive squares in 4 ways, for example, as 88228449 + 73427761 = 9393^2 + 8569^2 .

It is a super-2 number, since 2×161656210² = 52265460463128200, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9531 + ... + 20350.

Almost surely, 2^161656210 is an apocalyptic number.

161656210 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161656210 is a deficient number, since it is larger than the sum of its proper divisors (129872582).

161656210 is a wasteful number, since it uses less digits than its factorization.

161656210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30429.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 161656210 is about 12714.4095419331. The cubic root of 161656210 is about 544.7502825901.

The spelling of 161656210 in words is "one hundred sixty-one million, six hundred fifty-six thousand, two hundred ten".