21490282 has 16 divisors (see below), whose sum is σ = 35985312. Its totient is φ = 9540720.

The previous prime is 21490279. The next prime is 21490283. The reversal of 21490282 is 28209412.

It is a self number, because there is not a number n which added to its sum of digits gives 21490282.

It is not an unprimeable number, because it can be changed into a prime (21490283) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10413 + ... + 12304.

It is an arithmetic number, because the mean of its divisors is an integer number (2249082).

Almost surely, 2^21490282 is an apocalyptic number.

21490282 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21490282 is a deficient number, since it is larger than the sum of its proper divisors (14495030).

21490282 is a wasteful number, since it uses less digits than its factorization.

21490282 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22773.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 21490282 is about 4635.7612104163. The cubic root of 21490282 is about 278.0229869024.

Adding to 21490282 its reverse (28209412), we get a palindrome (49699694).

The spelling of 21490282 in words is "twenty-one million, four hundred ninety thousand, two hundred eighty-two".