21001220020012 has 6 divisors (see below), whose sum is σ = 36752135035028. Its totient is φ = 10500610010004.

The previous prime is 21001220020003. The next prime is 21001220020021. The reversal of 21001220020012 is 21002002210012.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21001220020003) and next prime (21001220020021).

It is a junction number, because it is equal to n+sod(n) for n = 21001220019974 and 21001220020001.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2625152502498 + ... + 2625152502505.

Almost surely, 2^{21001220020012} is an apocalyptic number.

It is an amenable number.

21001220020012 is a deficient number, since it is larger than the sum of its proper divisors (15750915015016).

21001220020012 is a wasteful number, since it uses less digits than its factorization.

21001220020012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5250305005007 (or 5250305005005 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21001220020012 its reverse (21002002210012), we get a palindrome (42003222230024).

The spelling of 21001220020012 in words is "twenty-one trillion, one billion, two hundred twenty million, twenty thousand, twelve".