25555420240400 has 90 divisors (see below), whose sum is σ = 63587036982222. Its totient is φ = 9869679411200.

The previous prime is 25555420240391. The next prime is 25555420240417. The reversal of 25555420240400 is 404202455552.

It can be written as a sum of positive squares in 9 ways, for example, as 7336557297664 + 18218862942736 = 2708608^2 + 4268356^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 37647281 + ... + 38320080.

Almost surely, 2^{25555420240400} is an apocalyptic number.

25555420240400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25555420240400 is an abundant number, since it is smaller than the sum of its proper divisors (38031616741822).

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

25555420240400 is a wasteful number, since it uses less digits than its factorization.

25555420240400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75967437 (or 75967397 counting only the distinct ones).

The product of its (nonzero) digits is 320000, while the sum is 38.

Adding to 25555420240400 its reverse (404202455552), we get a palindrome (25959622695952).

The spelling of 25555420240400 in words is "twenty-five trillion, five hundred fifty-five billion, four hundred twenty million, two hundred forty thousand, four hundred".