21795680 has 24 divisors (see below), whose sum is σ = 51492672. Its totient is φ = 8718208.

The previous prime is 21795677. The next prime is 21795691. The reversal of 21795680 is 8659712.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 67952 + ... + 68271.

It is an arithmetic number, because the mean of its divisors is an integer number (2145528).

Almost surely, 2^21795680 is an apocalyptic number.

21795680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21795680 is an abundant number, since it is smaller than the sum of its proper divisors (29696992).

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

21795680 is a wasteful number, since it uses less digits than its factorization.

21795680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136238 (or 136230 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 38.

The square root of 21795680 is about 4668.5843678786. The cubic root of 21795680 is about 279.3337902804. Note that the first 3 decimals are identical.

The spelling of 21795680 in words is "twenty-one million, seven hundred ninety-five thousand, six hundred eighty".