25209098640 has 400 divisors, whose sum is σ = 96687936576. Its totient is φ = 6036249600.

The previous prime is 25209098573. The next prime is 25209098657. The reversal of 25209098640 is 4689090252.

25209098640 is a `hidden beast` number, since 2 + 520 + 9 + 0 + 9 + 86 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 5914110 + ... + 5918370.

Almost surely, 2^25209098640 is an apocalyptic number.

25209098640 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 25209098640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48343968288).

25209098640 is an abundant number, since it is smaller than the sum of its proper divisors (71478837936).

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

25209098640 is a wasteful number, since it uses less digits than its factorization.

25209098640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4380 (or 4365 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The spelling of 25209098640 in words is "twenty-five billion, two hundred nine million, ninety-eight thousand, six hundred forty".