21021717202 has 8 divisors (see below), whose sum is σ = 31547505276. Its totient is φ = 10505882112.

The previous prime is 21021717109. The next prime is 21021717239. The reversal of 21021717202 is 20271712012.

It can be written as a sum of positive squares in 2 ways, for example, as 19799585521 + 1222131681 = 140711^2 + 34959^2 .

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, 2482963 + ... + 2491414.

Almost surely, 2^21021717202 is an apocalyptic number.

21021717202 is a deficient number, since it is larger than the sum of its proper divisors (10525788074).

21021717202 is a wasteful number, since it uses less digits than its factorization.

21021717202 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4976492.

The product of its (nonzero) digits is 784, while the sum is 25.

The spelling of 21021717202 in words is "twenty-one billion, twenty-one million, seven hundred seventeen thousand, two hundred two".