25555645500 has 192 divisors, whose sum is σ = 92781351936. Its totient is φ = 5310240000.

The previous prime is 25555645441. The next prime is 25555645517. The reversal of 25555645500 is 554655552.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4870 + ... + 226130.

It is an arithmetic number, because the mean of its divisors is an integer number (483236208).

Almost surely, 2^25555645500 is an apocalyptic number.

25555645500 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 25555645500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46390675968).

25555645500 is an abundant number, since it is smaller than the sum of its proper divisors (67225706436).

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

25555645500 is a wasteful number, since it uses less digits than its factorization.

25555645500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221301 (or 221289 counting only the distinct ones).

The product of its (nonzero) digits is 750000, while the sum is 42.

The spelling of 25555645500 in words is "twenty-five billion, five hundred fifty-five million, six hundred forty-five thousand, five hundred".