25220240400 has 120 divisors (see below), whose sum is σ = 80826465664. Its totient is φ = 6722265600.

The previous prime is 25220240399. The next prime is 25220240407. The reversal of 25220240400 is 404202252.

It is a tau number, because it is divible by the number of its divisors (120).

It is not an unprimeable number, because it can be changed into a prime (25220240407) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3813897 + ... + 3820503.

Almost surely, 2^25220240400 is an apocalyptic number.

25220240400 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 25220240400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40413232832).

25220240400 is an abundant number, since it is smaller than the sum of its proper divisors (55606225264).

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

25220240400 is a wasteful number, since it uses less digits than its factorization.

25220240400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9809 (or 9798 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 21.

Adding to 25220240400 its reverse (404202252), we get a palindrome (25624442652).

The spelling of 25220240400 in words is "twenty-five billion, two hundred twenty million, two hundred forty thousand, four hundred".