16661172257472 has 112 divisors (see below), whose sum is σ = 44474421063680. Its totient is φ = 5504459369472.

The previous prime is 16661172257461. The next prime is 16661172257479. The reversal of 16661172257472 is 27475227116661.

It is not an unprimeable number, because it can be changed into a prime (16661172257479) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23968179 + ... + 24653517.

Almost surely, 2^{16661172257472} is an apocalyptic number.

16661172257472 is a gapful number since it is divisible by the number (12) 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 16661172257472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22237210531840).

16661172257472 is an abundant number, since it is smaller than the sum of its proper divisors (27813248806208).

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

16661172257472 is a wasteful number, since it uses less digits than its factorization.

16661172257472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 686478 (or 686468 counting only the distinct ones).

The product of its digits is 11854080, while the sum is 57.

The spelling of 16661172257472 in words is "sixteen trillion, six hundred sixty-one billion, one hundred seventy-two million, two hundred fifty-seven thousand, four hundred seventy-two".