21001222010 has 8 divisors (see below), whose sum is σ = 37802199636. Its totient is φ = 8400488800.

The previous prime is 21001222009. The next prime is 21001222049. The reversal of 21001222010 is 1022210012.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 20978915281 + 22306729 = 144841^2 + 4723^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 21001221982 and 21001222000.

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, 1050061091 + ... + 1050061110.

Almost surely, 2^21001222010 is an apocalyptic number.

21001222010 is a deficient number, since it is larger than the sum of its proper divisors (16800977626).

21001222010 is a wasteful number, since it uses less digits than its factorization.

21001222010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2100122208.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21001222010 its reverse (1022210012), we get a palindrome (22023432022).

The spelling of 21001222010 in words is "twenty-one billion, one million, two hundred twenty-two thousand, ten".