161272100 has 72 divisors (see below), whose sum is σ = 383892096. Its totient is φ = 58320000.

The previous prime is 161272099. The next prime is 161272117. The reversal of 161272100 is 1272161.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 297830 + ... + 298370.

Almost surely, 2^161272100 is an apocalyptic number.

161272100 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 161272100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (191946048).

161272100 is an abundant number, since it is smaller than the sum of its proper divisors (222619996).

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

161272100 is a wasteful number, since it uses less digits than its factorization.

161272100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 837 (or 830 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 20.

The square root of 161272100 is about 12699.2952560368. The cubic root of 161272100 is about 544.3184815108.

The spelling of 161272100 in words is "one hundred sixty-one million, two hundred seventy-two thousand, one hundred".