16661172535640 has 16 divisors (see below), whose sum is σ = 37487638205280. Its totient is φ = 6664469014240.

The previous prime is 16661172535561. The next prime is 16661172535661. The reversal of 16661172535640 is 4653527116661.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 208264656656 + ... + 208264656735.

It is an arithmetic number, because the mean of its divisors is an integer number (2342977387830).

Almost surely, 2^{16661172535640} is an apocalyptic number.

16661172535640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16661172535640 is an abundant number, since it is smaller than the sum of its proper divisors (20826465669640).

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

16661172535640 is a wasteful number, since it uses less digits than its factorization.

16661172535640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 416529313402 (or 416529313398 counting only the distinct ones).

The product of its (nonzero) digits is 5443200, while the sum is 53.

The spelling of 16661172535640 in words is "sixteen trillion, six hundred sixty-one billion, one hundred seventy-two million, five hundred thirty-five thousand, six hundred forty".