21210221000 has 32 divisors (see below), whose sum is σ = 49631919480. Its totient is φ = 8484088000.

The previous prime is 21210220991. The next prime is 21210221017. The reversal of 21210221000 is 12201212.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 968329924 + 20241891076 = 31118^2 + 142274^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10604111 + ... + 10606110.

Almost surely, 2^21210221000 is an apocalyptic number.

21210221000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21210221000 is an abundant number, since it is smaller than the sum of its proper divisors (28421698480).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21210221000 is a wasteful number, since it uses less digits than its factorization.

21210221000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21210242 (or 21210228 counting only the distinct ones).

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

Adding to 21210221000 its reverse (12201212), we get a palindrome (21222422212).

The spelling of 21210221000 in words is "twenty-one billion, two hundred ten million, two hundred twenty-one thousand".