21001211212112 has 20 divisors (see below), whose sum is σ = 40690796512596. Its totient is φ = 10500360499200.

The previous prime is 21001211212067. The next prime is 21001211212187. The reversal of 21001211212112 is 21121211210012.

It can be written as a sum of positive squares in 2 ways, for example, as 12442099256896 + 8559111955216 = 3527336^2 + 2925596^2 .

It is a congruent 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, 14611313 + ... + 15984144.

Almost surely, 2^{21001211212112} is an apocalyptic number.

It is an amenable number.

21001211212112 is a deficient number, since it is larger than the sum of its proper divisors (19689585300484).

21001211212112 is a wasteful number, since it uses less digits than its factorization.

21001211212112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30638366 (or 30638360 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21001211212112 its reverse (21121211210012), we get a palindrome (42122422422124).

The spelling of 21001211212112 in words is "twenty-one trillion, one billion, two hundred eleven million, two hundred twelve thousand, one hundred twelve".