21890248 has 16 divisors (see below), whose sum is σ = 41298480. Its totient is φ = 10877328.

The previous prime is 21890243. The next prime is 21890257. The reversal of 21890248 is 84209812.

It is not an unprimeable number, because it can be changed into a prime (21890243) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7090 + ... + 9697.

It is an arithmetic number, because the mean of its divisors is an integer number (2581155).

Almost surely, 2^21890248 is an apocalyptic number.

It is an amenable number.

21890248 is a deficient number, since it is larger than the sum of its proper divisors (19408232).

21890248 is a wasteful number, since it uses less digits than its factorization.

21890248 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16956 (or 16952 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 34.

The square root of 21890248 is about 4678.7015292707. The cubic root of 21890248 is about 279.7372024047.

The spelling of 21890248 in words is "twenty-one million, eight hundred ninety thousand, two hundred forty-eight".