21131221002 has 8 divisors (see below), whose sum is σ = 42262442016. Its totient is φ = 7043740332.

The previous prime is 21131220989. The next prime is 21131221063. The reversal of 21131221002 is 20012213112.

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

21131221002 is an admirable number.

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, 1760935078 + ... + 1760935089.

It is an arithmetic number, because the mean of its divisors is an integer number (5282805252).

Almost surely, 2^21131221002 is an apocalyptic number.

21131221002 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21131221002 is a wasteful number, since it uses less digits than its factorization.

21131221002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3521870172.

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21131221002 its reverse (20012213112), we get a palindrome (41143434114).

The spelling of 21131221002 in words is "twenty-one billion, one hundred thirty-one million, two hundred twenty-one thousand, two".