25770640 has 80 divisors (see below), whose sum is σ = 72531072. Its totient is φ = 8312832.

The previous prime is 25770637. The next prime is 25770643. The reversal of 25770640 is 4607752.

It is an interprime number because it is at equal distance from previous prime (25770637) and next prime (25770643).

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (25770643) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8167 + ... + 10873.

Almost surely, 2^25770640 is an apocalyptic number.

25770640 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 25770640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36265536).

25770640 is an abundant number, since it is smaller than the sum of its proper divisors (46760432).

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

25770640 is a wasteful number, since it uses less digits than its factorization.

25770640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2744 (or 2738 counting only the distinct ones).

The product of its (nonzero) digits is 11760, while the sum is 31.

The square root of 25770640 is about 5076.4790948058. The cubic root of 25770640 is about 295.3759068891.

The spelling of 25770640 in words is "twenty-five million, seven hundred seventy thousand, six hundred forty".