25247640 has 128 divisors (see below), whose sum is σ = 85432320. Its totient is φ = 5913600.

The previous prime is 25247639. The next prime is 25247699. The reversal of 25247640 is 4674252.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

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 = 25247598 and 25247607.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 40612 + ... + 41228.

It is an arithmetic number, because the mean of its divisors is an integer number (667440).

Almost surely, 2^25247640 is an apocalyptic number.

25247640 is a gapful number since it is divisible by the number (20) 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 25247640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42716160).

25247640 is an abundant number, since it is smaller than the sum of its proper divisors (60184680).

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

25247640 is a wasteful number, since it uses less digits than its factorization.

25247640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 673 (or 669 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 30.

The square root of 25247640 is about 5024.7029762962. The cubic root of 25247640 is about 293.3640750609.

The spelling of 25247640 in words is "twenty-five million, two hundred forty-seven thousand, six hundred forty".