161518680 has 192 divisors, whose sum is σ = 556657920. Its totient is φ = 40550400.

The previous prime is 161518663. The next prime is 161518703. The reversal of 161518680 is 86815161.

161518680 is a `hidden beast` number, since 1 + 61 + 518 + 6 + 80 = 666.

It is a Cunningham number, because it is equal to 12709²-1.

It is a super-3 number, since 3×161518680³ (a number of 26 digits) contains 333 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 47 ways as a sum of consecutive naturals, for example, 457384 + ... + 457736.

It is an arithmetic number, because the mean of its divisors is an integer number (2899260).

Almost surely, 2^161518680 is an apocalyptic number.

161518680 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 161518680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (278328960).

161518680 is an abundant number, since it is smaller than the sum of its proper divisors (395139240).

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

161518680 is a wasteful number, since it uses less digits than its factorization.

161518680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 442 (or 435 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 36.

The square root of 161518680 is about 12708.9999606578. Note that the first 4 decimals coincide. The cubic root of 161518680 is about 544.5957555592.

The spelling of 161518680 in words is "one hundred sixty-one million, five hundred eighteen thousand, six hundred eighty".