21002222221000 has 64 divisors (see below), whose sum is σ = 49145916858480. Its totient is φ = 8400766348800.

The previous prime is 21002222220953. The next prime is 21002222221009. The reversal of 21002222221000 is 12222220012.

It can be written as a sum of positive squares in 8 ways, for example, as 972712732644 + 20029509488356 = 986262^2 + 4475434^2 .

It is not an unprimeable number, because it can be changed into a prime (21002222221009) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 103471612 + ... + 103674388.

Almost surely, 2^{21002222221000} is an apocalyptic number.

21002222221000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21002222221000 is an abundant number, since it is smaller than the sum of its proper divisors (28143694637480).

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

21002222221000 is a wasteful number, since it uses less digits than its factorization.

21002222221000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 306371 (or 306357 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 21002222221000 its reverse (12222220012), we get a palindrome (21014444441012).

The spelling of 21002222221000 in words is "twenty-one trillion, two billion, two hundred twenty-two million, two hundred twenty-one thousand".