21001211212212 has 108 divisors (see below), whose sum is σ = 67367521742976. Its totient is φ = 5454860050080.

The previous prime is 21001211212187. The next prime is 21001211212279. The reversal of 21001211212212 is 21221211210012.

21001211212212 is a `hidden beast` number, since 210 + 0 + 1 + 211 + 21 + 221 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 541137348 + ... + 541176155.

It is an arithmetic number, because the mean of its divisors is an integer number (623773349472).

Almost surely, 2^{21001211212212} is an apocalyptic number.

21001211212212 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21001211212212 is an abundant number, since it is smaller than the sum of its proper divisors (46366310530764).

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

21001211212212 is a wasteful number, since it uses less digits than its factorization.

21001211212212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1082313538 (or 1082313526 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21001211212212 its reverse (21221211210012), we get a palindrome (42222422422224).

The spelling of 21001211212212 in words is "twenty-one trillion, one billion, two hundred eleven million, two hundred twelve thousand, two hundred twelve".