21763984 has 40 divisors (see below), whose sum is σ = 47496960. Its totient is φ = 9571200.

The previous prime is 21763967. The next prime is 21763991. The reversal of 21763984 is 48936712.

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, 3462 + ... + 7450.

It is an arithmetic number, because the mean of its divisors is an integer number (1187424).

Almost surely, 2^21763984 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21763984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23748480).

21763984 is an abundant number, since it is smaller than the sum of its proper divisors (25732976).

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

21763984 is a wasteful number, since it uses less digits than its factorization.

21763984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4039 (or 4033 counting only the distinct ones).

The product of its digits is 72576, while the sum is 40.

The square root of 21763984 is about 4665.1885278089. The cubic root of 21763984 is about 279.1983191060.

The spelling of 21763984 in words is "twenty-one million, seven hundred sixty-three thousand, nine hundred eighty-four".