25687978890 has 128 divisors (see below), whose sum is σ = 71784603648. Its totient is φ = 5761704960.

The previous prime is 25687978873. The next prime is 25687978951. The reversal of 25687978890 is 9887978652.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3809602 + ... + 3816338.

It is an arithmetic number, because the mean of its divisors is an integer number (560817216).

Almost surely, 2^25687978890 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 25687978890, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35892301824).

25687978890 is an abundant number, since it is smaller than the sum of its proper divisors (46096624758).

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

25687978890 is a wasteful number, since it uses less digits than its factorization.

25687978890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7092.

The product of its (nonzero) digits is 121927680, while the sum is 69.

The spelling of 25687978890 in words is "twenty-five billion, six hundred eighty-seven million, nine hundred seventy-eight thousand, eight hundred ninety".