21195680 has 48 divisors (see below), whose sum is σ = 54631584. Its totient is φ = 7706880.

The previous prime is 21195679. The next prime is 21195739. The reversal of 21195680 is 8659112.

It is a super-3 number, since 3×21195680³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (32).

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 7 ways as a sum of consecutive naturals, for example, 4262 + ... + 7781.

It is an arithmetic number, because the mean of its divisors is an integer number (1138158).

Almost surely, 2^21195680 is an apocalyptic number.

21195680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21195680 is an abundant number, since it is smaller than the sum of its proper divisors (33435904).

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

21195680 is a wasteful number, since it uses less digits than its factorization.

21195680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12069 (or 12061 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 21195680 is about 4603.8766273652. The cubic root of 21195680 is about 276.7467002857.

The spelling of 21195680 in words is "twenty-one million, one hundred ninety-five thousand, six hundred eighty".