21001211221010 has 16 divisors (see below), whose sum is σ = 37813528855872. Its totient is φ = 8397962564400.

The previous prime is 21001211221009. The next prime is 21001211221021. The reversal of 21001211221010 is 1012211210012.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 315205526 + ... + 315272145.

It is an arithmetic number, because the mean of its divisors is an integer number (2363345553492).

Almost surely, 2^{21001211221010} is an apocalyptic number.

21001211221010 is a deficient number, since it is larger than the sum of its proper divisors (16812317634862).

21001211221010 is a wasteful number, since it uses less digits than its factorization.

21001211221010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 630481009.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21001211221010 its reverse (1012211210012), we get a palindrome (22013422431022).

The spelling of 21001211221010 in words is "twenty-one trillion, one billion, two hundred eleven million, two hundred twenty-one thousand, ten".