21098338 has 4 divisors (see below), whose sum is σ = 31647510. Its totient is φ = 10549168.

The previous prime is 21098327. The next prime is 21098339. The reversal of 21098338 is 83389012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 18464209 + 2634129 = 4297^2 + 1623^2 .

It is not an unprimeable number, because it can be changed into a prime (21098339) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5274583 + ... + 5274586.

Almost surely, 2^21098338 is an apocalyptic number.

21098338 is a deficient number, since it is larger than the sum of its proper divisors (10549172).

21098338 is a wasteful number, since it uses less digits than its factorization.

21098338 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10549171.

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

The square root of 21098338 is about 4593.2927187367. The cubic root of 21098338 is about 276.3223933447.

The spelling of 21098338 in words is "twenty-one million, ninety-eight thousand, three hundred thirty-eight".