16660881 has 12 divisors (see below), whose sum is σ = 24190452. Its totient is φ = 11049696.

The previous prime is 16660879. The next prime is 16660907. The reversal of 16660881 is 18806661.

It can be written as a sum of positive squares in 2 ways, for example, as 7750656 + 8910225 = 2784^2 + 2985^2 .

It is not a de Polignac number, because 16660881 - 2¹ = 16660879 is a prime.

It is a super-2 number, since 2×16660881² = 555169911392322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (16660871) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2926 + ... + 6471.

It is an arithmetic number, because the mean of its divisors is an integer number (2015871).

Almost surely, 2^16660881 is an apocalyptic number.

It is an amenable number.

16660881 is a deficient number, since it is larger than the sum of its proper divisors (7529571).

16660881 is a wasteful number, since it uses less digits than its factorization.

16660881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9600 (or 9597 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 16660881 is about 4081.7742465746. The cubic root of 16660881 is about 255.4069166374.

The spelling of 16660881 in words is "sixteen million, six hundred sixty thousand, eight hundred eighty-one".