212111021209 has 4 divisors (see below), whose sum is σ = 214170351616. Its totient is φ = 210051690804.

The previous prime is 212111021203. The next prime is 212111021219. The reversal of 212111021209 is 902120111212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 212111021209 - 2¹⁷ = 212110890137 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 212111021209.

It is not an unprimeable number, because it can be changed into a prime (212111021203) 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, 1029665049 + ... + 1029665254.

It is an arithmetic number, because the mean of its divisors is an integer number (53542587904).

Almost surely, 2^212111021209 is an apocalyptic number.

It is an amenable number.

212111021209 is a deficient number, since it is larger than the sum of its proper divisors (2059330407).

212111021209 is a wasteful number, since it uses less digits than its factorization.

212111021209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2059330406.

The product of its (nonzero) digits is 144, while the sum is 22.

The spelling of 212111021209 in words is "two hundred twelve billion, one hundred eleven million, twenty-one thousand, two hundred nine".