161785175040 has 220 divisors, whose sum is σ = 579748081176. Its totient is φ = 43142602752.

The previous prime is 161785175023. The next prime is 161785175053. The reversal of 161785175040 is 40571587161.

161785175040 is a `hidden beast` number, since 1 + 61 + 7 + 85 + 1 + 7 + 504 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 219667 + ... + 609773.

Almost surely, 2^161785175040 is an apocalyptic number.

161785175040 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 161785175040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (289874040588).

161785175040 is an abundant number, since it is smaller than the sum of its proper divisors (417962906136).

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

161785175040 is an equidigital number, since it uses as much as digits as its factorization.

161785175040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 390144 (or 390117 counting only the distinct ones).

The product of its (nonzero) digits is 235200, while the sum is 45.

The spelling of 161785175040 in words is "one hundred sixty-one billion, seven hundred eighty-five million, one hundred seventy-five thousand, forty".