21481488 has 120 divisors (see below), whose sum is σ = 69715776. Its totient is φ = 6048000.

The previous prime is 21481469. The next prime is 21481501. The reversal of 21481488 is 88418412.

It is a happy number.

It is a super-2 number, since 2×21481488² = 922908653388288, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 101703 + ... + 101913.

Almost surely, 2^21481488 is an apocalyptic number.

21481488 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21481488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34857888).

21481488 is an abundant number, since it is smaller than the sum of its proper divisors (48234288).

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

21481488 is a wasteful number, since it uses less digits than its factorization.

21481488 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333 (or 324 counting only the distinct ones).

The product of its digits is 16384, while the sum is 36.

The square root of 21481488 is about 4634.8126175715. The cubic root of 21481488 is about 277.9850586314.

The spelling of 21481488 in words is "twenty-one million, four hundred eighty-one thousand, four hundred eighty-eight".