161689020 has 48 divisors (see below), whose sum is σ = 454210848. Its totient is φ = 42976000.

The previous prime is 161689013. The next prime is 161689037. The reversal of 161689020 is 20986161.

It is a super-2 number, since 2×161689020² = 52286678377120800, which contains 22 as substring.

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, 14770 + ... + 23270.

It is an arithmetic number, because the mean of its divisors is an integer number (9462726).

Almost surely, 2^161689020 is an apocalyptic number.

161689020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161689020 is an abundant number, since it is smaller than the sum of its proper divisors (292521828).

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

161689020 is a wasteful number, since it uses less digits than its factorization.

161689020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8830 (or 8828 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 161689020 is about 12715.6997448037. The cubic root of 161689020 is about 544.7871345566.

The spelling of 161689020 in words is "one hundred sixty-one million, six hundred eighty-nine thousand, twenty".