16561884123732 has 24 divisors (see below), whose sum is σ = 39890989718272. Its totient is φ = 5342543265600.

The previous prime is 16561884123731. The next prime is 16561884123751. The reversal of 16561884123732 is 23732148816561.

It is a happy number.

It is a Smith number, since the sum of its digits (57) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16561884123731) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22260596569 + ... + 22260597312.

Almost surely, 2^{16561884123732} is an apocalyptic number.

16561884123732 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

16561884123732 is an abundant number, since it is smaller than the sum of its proper divisors (23329105594540).

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

16561884123732 is a wasteful number, since it uses less digits than its factorization.

16561884123732 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44521193919 (or 44521193917 counting only the distinct ones).

The product of its digits is 11612160, while the sum is 57.

The spelling of 16561884123732 in words is "sixteen trillion, five hundred sixty-one billion, eight hundred eighty-four million, one hundred twenty-three thousand, seven hundred thirty-two".