21898330 has 16 divisors (see below), whose sum is σ = 39562344. Its totient is φ = 8727040.

The previous prime is 21898319. The next prime is 21898333. The reversal of 21898330 is 3389812.

It can be written as a sum of positive squares in 4 ways, for example, as 21818241 + 80089 = 4671^2 + 283^2 .

It is not an unprimeable number, because it can be changed into a prime (21898333) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 1087 + ... + 6706.

Almost surely, 2^21898330 is an apocalyptic number.

21898330 is a deficient number, since it is larger than the sum of its proper divisors (17664014).

21898330 is a wasteful number, since it uses less digits than its factorization.

21898330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8081.

The product of its (nonzero) digits is 10368, while the sum is 34.

The square root of 21898330 is about 4679.5651507378. The cubic root of 21898330 is about 279.7716250068.

The spelling of 21898330 in words is "twenty-one million, eight hundred ninety-eight thousand, three hundred thirty".