21485884 has 24 divisors (see below), whose sum is σ = 45234560. Its totient is φ = 8723376.

The previous prime is 21485881. The next prime is 21485899. The reversal of 21485884 is 48858412.

It is a super-2 number, since 2×21485884² = 923286422522912, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21485881) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19662 + ... + 20725.

Almost surely, 2^21485884 is an apocalyptic number.

It is an amenable number.

21485884 is an abundant number, since it is smaller than the sum of its proper divisors (23748676).

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

21485884 is a wasteful number, since it uses less digits than its factorization.

21485884 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40417 (or 40415 counting only the distinct ones).

The product of its digits is 81920, while the sum is 40.

The square root of 21485884 is about 4635.2868303914. The cubic root of 21485884 is about 278.0040197476.

The spelling of 21485884 in words is "twenty-one million, four hundred eighty-five thousand, eight hundred eighty-four".