12917640 has 32 divisors (see below), whose sum is σ = 38753280. Its totient is φ = 3444672.

The previous prime is 12917633. The next prime is 12917647. The reversal of 12917640 is 4671921.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (12917633) and next prime (12917647).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 12917598 and 12917607.

It is not an unprimeable number, because it can be changed into a prime (12917647) 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, 53704 + ... + 53943.

It is an arithmetic number, because the mean of its divisors is an integer number (1211040).

Almost surely, 2^12917640 is an apocalyptic number.

12917640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12917640 is an abundant number, since it is smaller than the sum of its proper divisors (25835640).

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

12917640 is a wasteful number, since it uses less digits than its factorization.

12917640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107661 (or 107657 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 12917640 is about 3594.1118513480. Note that the first 3 decimals coincide. The cubic root of 12917640 is about 234.6358627926.

The spelling of 12917640 in words is "twelve million, nine hundred seventeen thousand, six hundred forty".