21021202210 has 8 divisors (see below), whose sum is σ = 37838163996. Its totient is φ = 8408480880.

The previous prime is 21021202201. The next prime is 21021202243. The reversal of 21021202210 is 1220212012.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 20015741529 + 1005460681 = 141477^2 + 31709^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1051060101 + ... + 1051060120.

Almost surely, 2^21021202210 is an apocalyptic number.

21021202210 is a deficient number, since it is larger than the sum of its proper divisors (16816961786).

21021202210 is a wasteful number, since it uses less digits than its factorization.

21021202210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2102120228.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21021202210 its reverse (1220212012), we get a palindrome (22241414222).

The spelling of 21021202210 in words is "twenty-one billion, twenty-one million, two hundred two thousand, two hundred ten".