25420640 has 48 divisors (see below), whose sum is σ = 68638752. Its totient is φ = 8715264.

The previous prime is 25420621. The next prime is 25420643. The reversal of 25420640 is 4602452.

It is a super-3 number, since 3×25420640³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25420643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10229 + ... + 12468.

It is an arithmetic number, because the mean of its divisors is an integer number (1429974).

Almost surely, 2^25420640 is an apocalyptic number.

25420640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25420640 is an abundant number, since it is smaller than the sum of its proper divisors (43218112).

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

25420640 is a wasteful number, since it uses less digits than its factorization.

25420640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22719 (or 22711 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 23.

The square root of 25420640 is about 5041.8885350630. Note that the first 3 decimals coincide. The cubic root of 25420640 is about 294.0326062530.

The spelling of 25420640 in words is "twenty-five million, four hundred twenty thousand, six hundred forty".