21768282 has 24 divisors (see below), whose sum is σ = 47379540. Its totient is φ = 7223040.

The previous prime is 21768269. The next prime is 21768289. The reversal of 21768282 is 28286712.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 21706281 + 62001 = 4659^2 + 249^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21768289) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1482 + ... + 6762.

Almost surely, 2^21768282 is an apocalyptic number.

21768282 is an abundant number, since it is smaller than the sum of its proper divisors (25611258).

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

21768282 is a wasteful number, since it uses less digits than its factorization.

21768282 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5518 (or 5515 counting only the distinct ones).

The product of its digits is 21504, while the sum is 36.

The square root of 21768282 is about 4665.6491509757. The cubic root of 21768282 is about 279.2166967982.

The spelling of 21768282 in words is "twenty-one million, seven hundred sixty-eight thousand, two hundred eighty-two".