161647400 has 24 divisors (see below), whose sum is σ = 375830670. Its totient is φ = 64658880.

The previous prime is 161647399. The next prime is 161647417. The reversal of 161647400 is 4746161.

It can be written as a sum of positive squares in 3 ways, for example, as 158105476 + 3541924 = 12574^2 + 1882^2 .

It is a super-2 number, since 2×161647400² = 52259763853520000, which contains 22 as substring.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 403919 + ... + 404318.

Almost surely, 2^161647400 is an apocalyptic number.

161647400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161647400 is an abundant number, since it is smaller than the sum of its proper divisors (214183270).

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

161647400 is a wasteful number, since it uses less digits than its factorization.

161647400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 808253 (or 808244 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 161647400 is about 12714.0630799127. The cubic root of 161647400 is about 544.7403864094.

The spelling of 161647400 in words is "one hundred sixty-one million, six hundred forty-seven thousand, four hundred".