161720052 has 24 divisors (see below), whose sum is σ = 406373856. Its totient is φ = 49759968.

The previous prime is 161720047. The next prime is 161720071. The reversal of 161720052 is 250027161.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 518178 + ... + 518489.

It is an arithmetic number, because the mean of its divisors is an integer number (16932244).

Almost surely, 2^161720052 is an apocalyptic number.

161720052 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

161720052 is an abundant number, since it is smaller than the sum of its proper divisors (244653804).

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

161720052 is a wasteful number, since it uses less digits than its factorization.

161720052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1036687 (or 1036685 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 24.

The square root of 161720052 is about 12716.9199101040. The cubic root of 161720052 is about 544.8219848986.

The spelling of 161720052 in words is "one hundred sixty-one million, seven hundred twenty thousand, fifty-two".