12638740 has 12 divisors (see below), whose sum is σ = 26541396. Its totient is φ = 5055488.

The previous prime is 12638699. The next prime is 12638741. The reversal of 12638740 is 4783621.

It can be written as a sum of positive squares in 2 ways, for example, as 2979076 + 9659664 = 1726^2 + 3108^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12638741) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 315949 + ... + 315988.

It is an arithmetic number, because the mean of its divisors is an integer number (2211783).

Almost surely, 2^12638740 is an apocalyptic number.

12638740 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12638740 is an abundant number, since it is smaller than the sum of its proper divisors (13902656).

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

12638740 is a wasteful number, since it uses less digits than its factorization.

12638740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 631946 (or 631944 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 12638740 is about 3555.1005611656. The cubic root of 12638740 is about 232.9349164619.

The spelling of 12638740 in words is "twelve million, six hundred thirty-eight thousand, seven hundred forty".