21000548 has 12 divisors (see below), whose sum is σ = 38685360. Its totient is φ = 9947592.

The previous prime is 21000533. The next prime is 21000557. The reversal of 21000548 is 84500012.

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, 138086 + ... + 138237.

It is an arithmetic number, because the mean of its divisors is an integer number (3223780).

Almost surely, 2^21000548 is an apocalyptic number.

It is an amenable number.

21000548 is a deficient number, since it is larger than the sum of its proper divisors (17684812).

21000548 is a wasteful number, since it uses less digits than its factorization.

21000548 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 276346 (or 276344 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 21000548 is about 4582.6354862677. The cubic root of 21000548 is about 275.8948174433.

The spelling of 21000548 in words is "twenty-one million, five hundred forty-eight", and thus it is an aban number.