21147338 has 4 divisors (see below), whose sum is σ = 31721010. Its totient is φ = 10573668.

The previous prime is 21147319. The next prime is 21147341. The reversal of 21147338 is 83374112.

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., 19386409 + 1760929 = 4403^2 + 1327^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21147338.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5286833 + ... + 5286836.

Almost surely, 2^21147338 is an apocalyptic number.

21147338 is a deficient number, since it is larger than the sum of its proper divisors (10573672).

21147338 is a wasteful number, since it uses less digits than its factorization.

21147338 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10573671.

The product of its digits is 4032, while the sum is 29.

The square root of 21147338 is about 4598.6234896978. The cubic root of 21147338 is about 276.5361436553.

The spelling of 21147338 in words is "twenty-one million, one hundred forty-seven thousand, three hundred thirty-eight".