161807400 has 144 divisors (see below), whose sum is σ = 547120860. Its totient is φ = 42854400.

The previous prime is 161807389. The next prime is 161807413. The reversal of 161807400 is 4708161.

It is a happy number.

161807400 is a `hidden beast` number, since 1 + 618 + 0 + 7 + 40 + 0 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 82846404 + 78960996 = 9102^2 + 8886^2 .

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 35 ways as a sum of consecutive naturals, for example, 433614 + ... + 433986.

Almost surely, 2^161807400 is an apocalyptic number.

161807400 is a gapful number since it is divisible by the number (10) 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 161807400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (273560430).

161807400 is an abundant number, since it is smaller than the sum of its proper divisors (385313460).

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

161807400 is a wasteful number, since it uses less digits than its factorization.

161807400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 636 (or 624 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The square root of 161807400 is about 12720.3537686654. The cubic root of 161807400 is about 544.9200567307.

The spelling of 161807400 in words is "one hundred sixty-one million, eight hundred seven thousand, four hundred".