161613506880 has 336 divisors, whose sum is σ = 658826663040. Its totient is φ = 36940105728.

The previous prime is 161613506869. The next prime is 161613506911. The reversal of 161613506880 is 88605316161.

161613506880 is a `hidden beast` number, since 1 + 6 + 1 + 61 + 3 + 506 + 8 + 80 = 666.

It is a tau number, because it is divible by the number of its divisors (336).

It is a super-2 number, since 2×161613506880² (a number of 23 digits) contains 22 as substring.

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 47 ways as a sum of consecutive naturals, for example, 395866 + ... + 692774.

It is an arithmetic number, because the mean of its divisors is an integer number (1960793640).

Almost surely, 2^161613506880 is an apocalyptic number.

161613506880 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 161613506880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (329413331520).

161613506880 is an abundant number, since it is smaller than the sum of its proper divisors (497213156160).

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

161613506880 is an equidigital number, since it uses as much as digits as its factorization.

161613506880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 296948 (or 296926 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The spelling of 161613506880 in words is "one hundred sixty-one billion, six hundred thirteen million, five hundred six thousand, eight hundred eighty".