21221001202012 has 12 divisors (see below), whose sum is σ = 37152349244136. Its totient is φ = 10606044275120.

The previous prime is 21221001202007. The next prime is 21221001202013. The reversal of 21221001202012 is 21020210012212.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221001202013) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1114070758 + ... + 1114089805.

It is an arithmetic number, because the mean of its divisors is an integer number (3096029103678).

Almost surely, 2^{21221001202012} is an apocalyptic number.

It is an amenable number.

21221001202012 is a deficient number, since it is larger than the sum of its proper divisors (15931348042124).

21221001202012 is a wasteful number, since it uses less digits than its factorization.

21221001202012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2228162948 (or 2228162946 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21221001202012 its reverse (21020210012212), we get a palindrome (42241211214224).

The spelling of 21221001202012 in words is "twenty-one trillion, two hundred twenty-one billion, one million, two hundred two thousand, twelve".