25693640 has 48 divisors (see below), whose sum is σ = 67254300. Its totient is φ = 8808576.

The previous prime is 25693639. The next prime is 25693649. The reversal of 25693640 is 4639652.

25693640 = 708² + 709² + ... + 755².

It can be written as a sum of positive squares in 2 ways, for example, as 25260676 + 432964 = 5026^2 + 658^2 .

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 25693640.

It is not an unprimeable number, because it can be changed into a prime (25693649) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4595 + ... + 8514.

Almost surely, 2^25693640 is an apocalyptic number.

25693640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25693640 is an abundant number, since it is smaller than the sum of its proper divisors (41560660).

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

25693640 is a wasteful number, since it uses less digits than its factorization.

25693640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13134 (or 13123 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 35.

The square root of 25693640 is about 5068.8894247162. The cubic root of 25693640 is about 295.0814292111.

The spelling of 25693640 in words is "twenty-five million, six hundred ninety-three thousand, six hundred forty".