161577280 has 28 divisors (see below), whose sum is σ = 384756660. Its totient is φ = 64630784.

The previous prime is 161577263. The next prime is 161577281. The reversal of 161577280 is 82775161.

It can be written as a sum of positive squares in 2 ways, for example, as 98724096 + 62853184 = 9936^2 + 7928^2 .

It is a super-2 number, since 2×161577280² = 52214434824396800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161577281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 252145 + ... + 252784.

Almost surely, 2^161577280 is an apocalyptic number.

161577280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161577280 is an abundant number, since it is smaller than the sum of its proper divisors (223179380).

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

161577280 is an equidigital number, since it uses as much as digits as its factorization.

161577280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 504946 (or 504936 counting only the distinct ones).

The product of its (nonzero) digits is 23520, while the sum is 37.

The square root of 161577280 is about 12711.3052044233. The cubic root of 161577280 is about 544.6616085255.

The spelling of 161577280 in words is "one hundred sixty-one million, five hundred seventy-seven thousand, two hundred eighty".