161553100 has 72 divisors (see below), whose sum is σ = 368101440. Its totient is φ = 61470720.

The previous prime is 161553089. The next prime is 161553103. The reversal of 161553100 is 1355161.

It is a super-2 number, since 2×161553100² = 52198808239220000, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161553103) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 173436 + ... + 174364.

It is an arithmetic number, because the mean of its divisors is an integer number (5112520).

Almost surely, 2^161553100 is an apocalyptic number.

161553100 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 161553100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (184050720).

161553100 is an abundant number, since it is smaller than the sum of its proper divisors (206548340).

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

161553100 is a wasteful number, since it uses less digits than its factorization.

161553100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1027 (or 1020 counting only the distinct ones).

The product of its (nonzero) digits is 450, while the sum is 22.

The square root of 161553100 is about 12710.3540469965. The cubic root of 161553100 is about 544.6344376784.

The spelling of 161553100 in words is "one hundred sixty-one million, five hundred fifty-three thousand, one hundred".