161173820 has 12 divisors (see below), whose sum is σ = 338465064. Its totient is φ = 64469520.

The previous prime is 161173819. The next prime is 161173823. The reversal of 161173820 is 28371161.

161173820 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161173823) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4029326 + ... + 4029365.

It is an arithmetic number, because the mean of its divisors is an integer number (28205422).

Almost surely, 2^161173820 is an apocalyptic number.

161173820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161173820 is an abundant number, since it is smaller than the sum of its proper divisors (177291244).

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

161173820 is a wasteful number, since it uses less digits than its factorization.

161173820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8058700 (or 8058698 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 29.

The square root of 161173820 is about 12695.4251602693. The cubic root of 161173820 is about 544.2078889349.

The spelling of 161173820 in words is "one hundred sixty-one million, one hundred seventy-three thousand, eight hundred twenty".