21683488 has 24 divisors (see below), whose sum is σ = 43118460. Its totient is φ = 10732800.

The previous prime is 21683437. The next prime is 21683491. The reversal of 21683488 is 88438612.

It can be written as a sum of positive squares in 2 ways, for example, as 18766224 + 2917264 = 4332^2 + 1708^2 .

It is a super-2 number, since 2×21683488² = 940347303692288, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21683488.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 123 + ... + 6586.

Almost surely, 2^21683488 is an apocalyptic number.

It is an amenable number.

21683488 is a deficient number, since it is larger than the sum of its proper divisors (21434972).

21683488 is a wasteful number, since it uses less digits than its factorization.

21683488 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6820 (or 6812 counting only the distinct ones).

The product of its digits is 73728, while the sum is 40.

The square root of 21683488 is about 4656.5532317370. The cubic root of 21683488 is about 278.8536807232.

The spelling of 21683488 in words is "twenty-one million, six hundred eighty-three thousand, four hundred eighty-eight".