12990640 has 40 divisors (see below), whose sum is σ = 32529168. Its totient is φ = 4796160.

The previous prime is 12990631. The next prime is 12990641. The reversal of 12990640 is 4609921.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (12990641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5206 + ... + 7285.

Almost surely, 2^12990640 is an apocalyptic number.

12990640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12990640 is an abundant number, since it is smaller than the sum of its proper divisors (19538528).

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

12990640 is a wasteful number, since it uses less digits than its factorization.

12990640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12517 (or 12511 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 12990640 is about 3604.2530432810. The cubic root of 12990640 is about 235.0770231905.

The spelling of 12990640 in words is "twelve million, nine hundred ninety thousand, six hundred forty".