161625798 has 12 divisors (see below), whose sum is σ = 350189268. Its totient is φ = 53875260.

The previous prime is 161625791. The next prime is 161625823. The reversal of 161625798 is 897526161.

161625798 is a `hidden beast` number, since 1 + 616 + 25 + 7 + 9 + 8 = 666.

It is a super-2 number, since 2×161625798² = 52245797158273608, which contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161625791) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 4489588 + ... + 4489623.

It is an arithmetic number, because the mean of its divisors is an integer number (29182439).

Almost surely, 2^161625798 is an apocalyptic number.

161625798 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

161625798 is an abundant number, since it is smaller than the sum of its proper divisors (188563470).

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

161625798 is a wasteful number, since it uses less digits than its factorization.

161625798 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8979219 (or 8979216 counting only the distinct ones).

The product of its digits is 181440, while the sum is 45.

The square root of 161625798 is about 12713.2135197990. The cubic root of 161625798 is about 544.7161195874.

The spelling of 161625798 in words is "one hundred sixty-one million, six hundred twenty-five thousand, seven hundred ninety-eight".