25229640 has 32 divisors (see below), whose sum is σ = 75689280. Its totient is φ = 6727872.

The previous prime is 25229609. The next prime is 25229641. The reversal of 25229640 is 4692252.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its 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 = 25229598 and 25229607.

It is not an unprimeable number, because it can be changed into a prime (25229641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 105004 + ... + 105243.

It is an arithmetic number, because the mean of its divisors is an integer number (2365290).

Almost surely, 2^25229640 is an apocalyptic number.

25229640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25229640 is an abundant number, since it is smaller than the sum of its proper divisors (50459640).

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

25229640 is a wasteful number, since it uses less digits than its factorization.

25229640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210261 (or 210257 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 25229640 is about 5022.9115062880. The cubic root of 25229640 is about 293.2943416951.

It can be divided in two parts, 252 and 29640, that added together give a palindrome (29892).

The spelling of 25229640 in words is "twenty-five million, two hundred twenty-nine thousand, six hundred forty".