13640725 has 24 divisors (see below), whose sum is σ = 20177280. Its totient is φ = 8944320.

The previous prime is 13640723. The next prime is 13640743. The reversal of 13640725 is 52704631.

It is not a de Polignac number, because 13640725 - 2¹ = 13640723 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 13640693 and 13640702.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13640723) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2331 + ... + 5719.

It is an arithmetic number, because the mean of its divisors is an integer number (840720).

Almost surely, 2^13640725 is an apocalyptic number.

It is an amenable number.

13640725 is a deficient number, since it is larger than the sum of its proper divisors (6536555).

13640725 is a wasteful number, since it uses less digits than its factorization.

13640725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3429 (or 3424 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 13640725 is about 3693.3352135976. The cubic root of 13640725 is about 238.9346588182.

It can be divided in two parts, 13640 and 725, that added together give a triangular number (14365 = T₁₆₉).

The spelling of 13640725 in words is "thirteen million, six hundred forty thousand, seven hundred twenty-five".