25617540 has 48 divisors (see below), whose sum is σ = 77249088. Its totient is φ = 6305664.

The previous prime is 25617523. The next prime is 25617547. The reversal of 25617540 is 4571652.

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 = 25617498 and 25617507.

It is not an unprimeable number, because it can be changed into a prime (25617547) 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, 15642 + ... + 17201.

It is an arithmetic number, because the mean of its divisors is an integer number (1609356).

Almost surely, 2^25617540 is an apocalyptic number.

25617540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25617540 is an abundant number, since it is smaller than the sum of its proper divisors (51631548).

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

25617540 is a wasteful number, since it uses less digits than its factorization.

25617540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32868 (or 32866 counting only the distinct ones).

The product of its (nonzero) digits is 8400, while the sum is 30.

The square root of 25617540 is about 5061.3772829142. The cubic root of 25617540 is about 294.7898148499.

It can be divided in two parts, 2561 and 7540, that added together give a palindrome (10101).

The spelling of 25617540 in words is "twenty-five million, six hundred seventeen thousand, five hundred forty".