161409511320 has 128 divisors (see below), whose sum is σ = 505502208000. Its totient is φ = 41153176064.

The previous prime is 161409511313. The next prime is 161409511321. The reversal of 161409511320 is 23115904161.

It is a super-2 number, since 2×161409511320² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161409511321) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7023769 + ... + 7046711.

It is an arithmetic number, because the mean of its divisors is an integer number (3949236000).

Almost surely, 2^161409511320 is an apocalyptic number.

161409511320 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 161409511320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (252751104000).

161409511320 is an abundant number, since it is smaller than the sum of its proper divisors (344092696680).

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

161409511320 is a wasteful number, since it uses less digits than its factorization.

161409511320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25529 (or 25525 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 33.

The spelling of 161409511320 in words is "one hundred sixty-one billion, four hundred nine million, five hundred eleven thousand, three hundred twenty".