16661172206440 has 64 divisors (see below), whose sum is σ = 40615880880960. Its totient is φ = 6126570562560.

The previous prime is 16661172206411. The next prime is 16661172206453. The reversal of 16661172206440 is 4460227116661.

It is a happy number.

16661172206440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 284874526 + ... + 284933005.

It is an arithmetic number, because the mean of its divisors is an integer number (634623138765).

Almost surely, 2^{16661172206440} is an apocalyptic number.

16661172206440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16661172206440 is an abundant number, since it is smaller than the sum of its proper divisors (23954708674520).

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

16661172206440 is a wasteful number, since it uses less digits than its factorization.

16661172206440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 569807602 (or 569807598 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 46.

The spelling of 16661172206440 in words is "sixteen trillion, six hundred sixty-one billion, one hundred seventy-two million, two hundred six thousand, four hundred forty".