25566420 has 48 divisors (see below), whose sum is σ = 78095808. Its totient is φ = 6197760.

The previous prime is 25566389. The next prime is 25566427. The reversal of 25566420 is 2466552.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25566427) 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 15 ways as a sum of consecutive naturals, for example, 18709 + ... + 20028.

It is an arithmetic number, because the mean of its divisors is an integer number (1626996).

Almost surely, 2^25566420 is an apocalyptic number.

25566420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25566420 is an abundant number, since it is smaller than the sum of its proper divisors (52529388).

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

25566420 is a wasteful number, since it uses less digits than its factorization.

25566420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38760 (or 38758 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 30.

The square root of 25566420 is about 5056.3247522286. The cubic root of 25566420 is about 294.5935991537.

The spelling of 25566420 in words is "twenty-five million, five hundred sixty-six thousand, four hundred twenty".