21344402 has 4 divisors (see below), whose sum is σ = 32016606. Its totient is φ = 10672200.

The previous prime is 21344369. The next prime is 21344417. The reversal of 21344402 is 20444312.

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., 15531481 + 5812921 = 3941^2 + 2411^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5336099 + ... + 5336102.

Almost surely, 2^21344402 is an apocalyptic number.

21344402 is a deficient number, since it is larger than the sum of its proper divisors (10672204).

21344402 is a wasteful number, since it uses less digits than its factorization.

21344402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10672203.

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 21344402 is about 4620.0002164502. Note that the first 3 decimals coincide. The cubic root of 21344402 is about 277.3924676022.

Adding to 21344402 its reverse (20444312), we get a palindrome (41788714).

The spelling of 21344402 in words is "twenty-one million, three hundred forty-four thousand, four hundred two".