25640780 has 24 divisors (see below), whose sum is σ = 58741200. Its totient is φ = 9323840.

The previous prime is 25640773. The next prime is 25640789. The reversal of 25640780 is 8704652.

It is not an unprimeable number, because it can be changed into a prime (25640789) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58055 + ... + 58494.

It is an arithmetic number, because the mean of its divisors is an integer number (2447550).

Almost surely, 2^25640780 is an apocalyptic number.

25640780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25640780 is an abundant number, since it is smaller than the sum of its proper divisors (33100420).

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

25640780 is a wasteful number, since it uses less digits than its factorization.

25640780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116569 (or 116567 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 32.

The square root of 25640780 is about 5063.6725802524. The cubic root of 25640780 is about 294.8789314557.

The spelling of 25640780 in words is "twenty-five million, six hundred forty thousand, seven hundred eighty".