21768298 has 4 divisors (see below), whose sum is σ = 32652450. Its totient is φ = 10884148.

The previous prime is 21768289. The next prime is 21768323. The reversal of 21768298 is 89286712.

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., 16184529 + 5583769 = 4023^2 + 2363^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5442073 + ... + 5442076.

Almost surely, 2^21768298 is an apocalyptic number.

21768298 is a deficient number, since it is larger than the sum of its proper divisors (10884152).

21768298 is a wasteful number, since it uses less digits than its factorization.

21768298 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10884151.

The product of its digits is 96768, while the sum is 43.

The square root of 21768298 is about 4665.6508656349. The cubic root of 21768298 is about 279.2167652076.

The spelling of 21768298 in words is "twenty-one million, seven hundred sixty-eight thousand, two hundred ninety-eight".