21986748 has 96 divisors (see below), whose sum is σ = 65945600. Its totient is φ = 6205248.

The previous prime is 21986747. The next prime is 21986777. The reversal of 21986748 is 84768912.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21986747) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 95898 + ... + 96126.

Almost surely, 2^21986748 is an apocalyptic number.

21986748 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 21986748, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32972800).

21986748 is an abundant number, since it is smaller than the sum of its proper divisors (43958852).

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

21986748 is a wasteful number, since it uses less digits than its factorization.

21986748 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 376 (or 368 counting only the distinct ones).

The product of its digits is 193536, while the sum is 45.

The square root of 21986748 is about 4689.0028790778. The cubic root of 21986748 is about 280.1476602118.

The spelling of 21986748 in words is "twenty-one million, nine hundred eighty-six thousand, seven hundred forty-eight".