12981661 has 16 divisors (see below), whose sum is σ = 16495488. Its totient is φ = 9921600.

The previous prime is 12981649. The next prime is 12981667. The reversal of 12981661 is 16618921.

12981661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 12981661 - 2¹⁵ = 12948893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12981667) 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, 2491 + ... + 5671.

It is an arithmetic number, because the mean of its divisors is an integer number (1030968).

Almost surely, 2^12981661 is an apocalyptic number.

12981661 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12981661 is a deficient number, since it is larger than the sum of its proper divisors (3513827).

12981661 is a wasteful number, since it uses less digits than its factorization.

12981661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3252.

The product of its digits is 5184, while the sum is 34.

The square root of 12981661 is about 3603.0072162015. The cubic root of 12981661 is about 235.0228497474.

The spelling of 12981661 in words is "twelve million, nine hundred eighty-one thousand, six hundred sixty-one".