161345520 has 200 divisors, whose sum is σ = 640610784. Its totient is φ = 36868608.

The previous prime is 161345497. The next prime is 161345533. The reversal of 161345520 is 25543161.

161345520 is a `hidden beast` number, since 1 + 6 + 134 + 5 + 520 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 43582 + ... + 47138.

Almost surely, 2^161345520 is an apocalyptic number.

161345520 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 161345520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (320305392).

161345520 is an abundant number, since it is smaller than the sum of its proper divisors (479265264).

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

161345520 is a wasteful number, since it uses less digits than its factorization.

161345520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3589 (or 3574 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 161345520 is about 12702.1856387001. The cubic root of 161345520 is about 544.4010702947.

Adding to 161345520 its reverse (25543161), we get a palindrome (186888681).

The spelling of 161345520 in words is "one hundred sixty-one million, three hundred forty-five thousand, five hundred twenty".