25291575540 has 384 divisors, whose sum is σ = 98380800000. Its totient is φ = 5240401920.

The previous prime is 25291575521. The next prime is 25291575541. The reversal of 25291575540 is 4557519252.

25291575540 is a `hidden beast` number, since 2 + 5 + 2 + 91 + 5 + 7 + 554 + 0 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25291575541) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 20248836 + ... + 20250084.

It is an arithmetic number, because the mean of its divisors is an integer number (256200000).

Almost surely, 2^25291575540 is an apocalyptic number.

25291575540 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 25291575540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49190400000).

25291575540 is an abundant number, since it is smaller than the sum of its proper divisors (73089224460).

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

25291575540 is a wasteful number, since it uses less digits than its factorization.

25291575540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1772 (or 1764 counting only the distinct ones).

The product of its (nonzero) digits is 630000, while the sum is 45.

It can be divided in two parts, 252915 and 75540, that added together give a triangular number (328455 = T₈₁₀).

The spelling of 25291575540 in words is "twenty-five billion, two hundred ninety-one million, five hundred seventy-five thousand, five hundred forty".