25218642 has 16 divisors (see below), whose sum is σ = 50958432. Its totient is φ = 8319360.

The previous prime is 25218607. The next prime is 25218647. The reversal of 25218642 is 24681252.

It is not an unprimeable number, because it can be changed into a prime (25218647) 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, 21084 + ... + 22247.

It is an arithmetic number, because the mean of its divisors is an integer number (3184902).

Almost surely, 2^25218642 is an apocalyptic number.

25218642 is an abundant number, since it is smaller than the sum of its proper divisors (25739790).

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

25218642 is a wasteful number, since it uses less digits than its factorization.

25218642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43433.

The product of its digits is 7680, while the sum is 30.

The square root of 25218642 is about 5021.8166035808. The cubic root of 25218642 is about 293.2517182835.

Adding to 25218642 its reverse (24681252), we get a palindrome (49899894).

The spelling of 25218642 in words is "twenty-five million, two hundred eighteen thousand, six hundred forty-two".