12990561 has 16 divisors (see below), whose sum is σ = 18385920. Its totient is φ = 8140880.

The previous prime is 12990557. The next prime is 12990583. The reversal of 12990561 is 16509921.

It is a cyclic number.

It is not a de Polignac number, because 12990561 - 2² = 12990557 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12990541) 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, 2476 + ... + 5666.

It is an arithmetic number, because the mean of its divisors is an integer number (1149120).

Almost surely, 2^12990561 is an apocalyptic number.

It is an amenable number.

12990561 is a deficient number, since it is larger than the sum of its proper divisors (5395359).

12990561 is a wasteful number, since it uses less digits than its factorization.

12990561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3276.

The product of its (nonzero) digits is 4860, while the sum is 33.

The square root of 12990561 is about 3604.2420839894. The cubic root of 12990561 is about 235.0765466647.

The spelling of 12990561 in words is "twelve million, nine hundred ninety thousand, five hundred sixty-one".