12717640 has 64 divisors (see below), whose sum is σ = 31696560. Its totient is φ = 4561920.

The previous prime is 12717623. The next prime is 12717647. The reversal of 12717640 is 4671721.

It can be written as a sum of positive squares in 8 ways, for example, as 7851204 + 4866436 = 2802^2 + 2206^2 .

It is a junction number, because it is equal to n+sod(n) for n = 12717599 and 12717608.

It is not an unprimeable number, because it can be changed into a prime (12717647) 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, 18910 + ... + 19570.

Almost surely, 2^12717640 is an apocalyptic number.

12717640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12717640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15848280).

12717640 is an abundant number, since it is smaller than the sum of its proper divisors (18978920).

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

12717640 is a wasteful number, since it uses less digits than its factorization.

12717640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 722 (or 718 counting only the distinct ones).

The product of its (nonzero) digits is 2352, while the sum is 28.

The square root of 12717640 is about 3566.1800291068. The cubic root of 12717640 is about 233.4186264144.

It can be divided in two parts, 1271 and 7640, that added together give a triangular number (8911 = T₁₃₃).

The spelling of 12717640 in words is "twelve million, seven hundred seventeen thousand, six hundred forty".