21221210221002 has 112 divisors (see below), whose sum is σ = 52551197161632. Its totient is φ = 6370569531360.

The previous prime is 21221210220949. The next prime is 21221210221007. The reversal of 21221210221002 is 20012201212212.

It is a happy number.

21221210221002 is a `hidden beast` number, since 21 + 221 + 210 + 2 + 210 + 0 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (21221210221007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 4467033 + ... + 7899164.

Almost surely, 2^{21221210221002} is an apocalyptic number.

21221210221002 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21221210221002 is an abundant number, since it is smaller than the sum of its proper divisors (31329986940630).

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

21221210221002 is a wasteful number, since it uses less digits than its factorization.

21221210221002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12366335 (or 12366320 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 21221210221002 its reverse (20012201212212), we get a palindrome (41233411433214).

The spelling of 21221210221002 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred ten million, two hundred twenty-one thousand, two".