25566540 has 48 divisors (see below), whose sum is σ = 71806560. Its totient is φ = 6796800.

The previous prime is 25566523. The next prime is 25566559. The reversal of 25566540 is 4566552.

It is a happy number.

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 35706 + ... + 36414.

It is an arithmetic number, because the mean of its divisors is an integer number (1495970).

Almost surely, 2^25566540 is an apocalyptic number.

25566540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25566540 is an abundant number, since it is smaller than the sum of its proper divisors (46240020).

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

25566540 is a wasteful number, since it uses less digits than its factorization.

25566540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1322 (or 1320 counting only the distinct ones).

The product of its (nonzero) digits is 36000, while the sum is 33.

The square root of 25566540 is about 5056.3366185411. The cubic root of 25566540 is about 294.5940600601.

It can be divided in two parts, 25566 and 540, that added together give a triangular number (26106 = T₂₂₈).

The spelling of 25566540 in words is "twenty-five million, five hundred sixty-six thousand, five hundred forty".