25821620 has 24 divisors (see below), whose sum is σ = 59155488. Its totient is φ = 9389600.

The previous prime is 25821619. The next prime is 25821637. The reversal of 25821620 is 2612852.

25821620 is an esthetic number in base 7, because in such base its adjacent digits differ by 1.

It is a self number, because there is not a number n which added to its sum of digits gives 25821620.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58466 + ... + 58905.

It is an arithmetic number, because the mean of its divisors is an integer number (2464812).

Almost surely, 2^25821620 is an apocalyptic number.

25821620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25821620 is an abundant number, since it is smaller than the sum of its proper divisors (33333868).

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

25821620 is a wasteful number, since it uses less digits than its factorization.

25821620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117391 (or 117389 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 25821620 is about 5081.4978106853. The cubic root of 25821620 is about 295.5705514551.

The spelling of 25821620 in words is "twenty-five million, eight hundred twenty-one thousand, six hundred twenty".