21340220402 has 8 divisors (see below), whose sum is σ = 32088596700. Its totient is φ = 10644021504.

The previous prime is 21340220399. The next prime is 21340220423. The reversal of 21340220402 is 20402204312.

It can be written as a sum of positive squares in 2 ways, for example, as 21315708001 + 24512401 = 145999^2 + 4951^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13043327 + ... + 13044962.

Almost surely, 2^21340220402 is an apocalyptic number.

21340220402 is a deficient number, since it is larger than the sum of its proper divisors (10748376298).

21340220402 is a wasteful number, since it uses less digits than its factorization.

21340220402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26088700.

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

Adding to 21340220402 its reverse (20402204312), we get a palindrome (41742424714).

The spelling of 21340220402 in words is "twenty-one billion, three hundred forty million, two hundred twenty thousand, four hundred two".