21000476 has 24 divisors (see below), whose sum is σ = 42287616. Its totient is φ = 8938800.

The previous prime is 21000467. The next prime is 21000481. The reversal of 21000476 is 67400012.

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, 1745 + ... + 6711.

It is an arithmetic number, because the mean of its divisors is an integer number (1761984).

Almost surely, 2^21000476 is an apocalyptic number.

It is an amenable number.

21000476 is an abundant number, since it is smaller than the sum of its proper divisors (21287140).

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

21000476 is a wasteful number, since it uses less digits than its factorization.

21000476 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5129 (or 5127 counting only the distinct ones).

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 21000476 is about 4582.6276305194. The cubic root of 21000476 is about 275.8945021429.

Adding to 21000476 its reverse (67400012), we get a palindrome (88400488).

The spelling of 21000476 in words is "twenty-one million, four hundred seventy-six", and thus it is an aban number.