161523203328 has 144 divisors (see below), whose sum is σ = 494123918400. Its totient is φ = 51984414720.

The previous prime is 161523203291. The next prime is 161523203363. The reversal of 161523203328 is 823302325161.

161523203328 is a `hidden beast` number, since 1 + 6 + 1 + 5 + 2 + 320 + 3 + 328 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

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

It is a junction number, because it is equal to n+sod(n) for n = 161523203292 and 161523203301.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 202458 + ... + 603353.

It is an arithmetic number, because the mean of its divisors is an integer number (3431416100).

Almost surely, 2^161523203328 is an apocalyptic number.

161523203328 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

161523203328 is an abundant number, since it is smaller than the sum of its proper divisors (332600715072).

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

161523203328 is an equidigital number, since it uses as much as digits as its factorization.

161523203328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 805865 (or 805845 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

Adding to 161523203328 its reverse (823302325161), we get a palindrome (984825528489).

The spelling of 161523203328 in words is "one hundred sixty-one billion, five hundred twenty-three million, two hundred three thousand, three hundred twenty-eight".