25851525840 has 480 divisors, whose sum is σ = 105022444800. Its totient is φ = 5907396096.

The previous prime is 25851525839. The next prime is 25851525863. The reversal of 25851525840 is 4852515852.

25851525840 is a `hidden beast` number, since 2 + 5 + 85 + 1 + 525 + 8 + 40 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 6665982 + ... + 6669858.

It is an arithmetic number, because the mean of its divisors is an integer number (218796760).

Almost surely, 2^25851525840 is an apocalyptic number.

25851525840 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 25851525840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52511222400).

25851525840 is an abundant number, since it is smaller than the sum of its proper divisors (79170918960).

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

25851525840 is an equidigital number, since it uses as much as digits as its factorization.

25851525840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3926 (or 3894 counting only the distinct ones).

The product of its (nonzero) digits is 640000, while the sum is 45.

The spelling of 25851525840 in words is "twenty-five billion, eight hundred fifty-one million, five hundred twenty-five thousand, eight hundred forty".