161687196 has 72 divisors (see below), whose sum is σ = 460282368. Its totient is φ = 47412000.

The previous prime is 161687173. The next prime is 161687203. The reversal of 161687196 is 691786161.

It is a super-2 number, since 2×161687196² = 52285498700684832, which contains 22 as substring.

It is a congruent number.

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 23 ways as a sum of consecutive naturals, for example, 5691 + ... + 18861.

Almost surely, 2^161687196 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161687196, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (230141184).

161687196 is an abundant number, since it is smaller than the sum of its proper divisors (298595172).

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

161687196 is a wasteful number, since it uses less digits than its factorization.

161687196 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13223 (or 13218 counting only the distinct ones).

The product of its digits is 108864, while the sum is 45.

The square root of 161687196 is about 12715.6280222410. The cubic root of 161687196 is about 544.7850859832.

The spelling of 161687196 in words is "one hundred sixty-one million, six hundred eighty-seven thousand, one hundred ninety-six".