161525665216 has 56 divisors (see below), whose sum is σ = 325737864144. Its totient is φ = 79458078720.

The previous prime is 161525665193. The next prime is 161525665237. The reversal of 161525665216 is 612566525161.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1217106 + ... + 1343278.

It is an arithmetic number, because the mean of its divisors is an integer number (5816747574).

Almost surely, 2^161525665216 is an apocalyptic number.

161525665216 is a gapful number since it is divisible by the number (16) 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 161525665216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (162868932072).

161525665216 is an abundant number, since it is smaller than the sum of its proper divisors (164212198928).

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

161525665216 is a wasteful number, since it uses less digits than its factorization.

161525665216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126509 (or 126499 counting only the distinct ones).

The product of its digits is 648000, while the sum is 46.

The spelling of 161525665216 in words is "one hundred sixty-one billion, five hundred twenty-five million, six hundred sixty-five thousand, two hundred sixteen".