161951664 has 120 divisors (see below), whose sum is σ = 500103408. Its totient is φ = 44997120.

The previous prime is 161951633. The next prime is 161951693. The reversal of 161951664 is 466159161.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 86094 + ... + 87954.

Almost surely, 2^161951664 is an apocalyptic number.

161951664 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161951664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (250051704).

161951664 is an abundant number, since it is smaller than the sum of its proper divisors (338151744).

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

161951664 is a wasteful number, since it uses less digits than its factorization.

161951664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1923 (or 1910 counting only the distinct ones).

The product of its digits is 38880, while the sum is 39.

The square root of 161951664 is about 12726.0231022893. The cubic root of 161951664 is about 545.0819549620.

The spelling of 161951664 in words is "one hundred sixty-one million, nine hundred fifty-one thousand, six hundred sixty-four".