161644275000 has 768 divisors, whose sum is σ = 613554480000. Its totient is φ = 39424320000.

The previous prime is 161644274927. The next prime is 161644275017. The reversal of 161644275000 is 572446161.

161644275000 is a `hidden beast` number, since 1 + 6 + 1 + 644 + 2 + 7 + 5 + 0 + 0 + 0 = 666.

It is a super-2 number, since 2×161644275000² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 1482974946 + ... + 1482975054.

Almost surely, 2^161644275000 is an apocalyptic number.

161644275000 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 161644275000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (306777240000).

161644275000 is an abundant number, since it is smaller than the sum of its proper divisors (451910205000).

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

161644275000 is an equidigital number, since it uses as much as digits as its factorization.

161644275000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188 (or 132 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The spelling of 161644275000 in words is "one hundred sixty-one billion, six hundred forty-four million, two hundred seventy-five thousand".