25644330 has 128 divisors (see below), whose sum is σ = 74856960. Its totient is φ = 6220800.

The previous prime is 25644329. The next prime is 25644337. The reversal of 25644330 is 3344652.

It is a super-2 number, since 2×25644330² = 1315263322297800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 25644294 and 25644303.

It is not an unprimeable number, because it can be changed into a prime (25644337) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 169755 + ... + 169905.

It is an arithmetic number, because the mean of its divisors is an integer number (584820).

Almost surely, 2^25644330 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 25644330, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37428480).

25644330 is an abundant number, since it is smaller than the sum of its proper divisors (49212630).

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

25644330 is a wasteful number, since it uses less digits than its factorization.

25644330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221 (or 215 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 27.

The square root of 25644330 is about 5064.0231042127. The cubic root of 25644330 is about 294.8925396208.

Adding to 25644330 its reverse (3344652), we get a palindrome (28988982).

The spelling of 25644330 in words is "twenty-five million, six hundred forty-four thousand, three hundred thirty".