25221680 has 40 divisors (see below), whose sum is σ = 63973584. Its totient is φ = 9171200.

The previous prime is 25221673. The next prime is 25221739. The reversal of 25221680 is 8612252.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×25221680² = 1272266284044800, which contains 22 as substring.

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, 13451 + ... + 15210.

Almost surely, 2^25221680 is an apocalyptic number.

25221680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25221680 is an abundant number, since it is smaller than the sum of its proper divisors (38751904).

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

25221680 is a wasteful number, since it uses less digits than its factorization.

25221680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28685 (or 28679 counting only the distinct ones).

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

The square root of 25221680 is about 5022.1190746536. The cubic root of 25221680 is about 293.2634934741.

The spelling of 25221680 in words is "twenty-five million, two hundred twenty-one thousand, six hundred eighty".