21212021214 has 24 divisors (see below), whose sum is σ = 45962116200. Its totient is φ = 7070252688.

The previous prime is 21212021161. The next prime is 21212021221. The reversal of 21212021214 is 41212021212.

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 11 ways as a sum of consecutive naturals, for example, 479712 + ... + 522060.

It is an arithmetic number, because the mean of its divisors is an integer number (1915088175).

Almost surely, 2^21212021214 is an apocalyptic number.

21212021214 is an abundant number, since it is smaller than the sum of its proper divisors (24750094986).

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

21212021214 is a wasteful number, since it uses less digits than its factorization.

21212021214 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70184 (or 70181 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 21212021214 its reverse (41212021212), we get a palindrome (62424042426).

The spelling of 21212021214 in words is "twenty-one billion, two hundred twelve million, twenty-one thousand, two hundred fourteen".