212021109 has 24 divisors (see below), whose sum is σ = 311101440. Its totient is φ = 139128192.

The previous prime is 212021099. The next prime is 212021113. The reversal of 212021109 is 901120212.

It is not a de Polignac number, because 212021109 - 2¹³ = 212012917 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 212021091 and 212021100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212021609) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 165132 + ... + 166410.

It is an arithmetic number, because the mean of its divisors is an integer number (12962560).

Almost surely, 2^212021109 is an apocalyptic number.

It is an amenable number.

212021109 is a deficient number, since it is larger than the sum of its proper divisors (99080331).

212021109 is a wasteful number, since it uses less digits than its factorization.

212021109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1561 (or 1558 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The square root of 212021109 is about 14560.9446465537. The cubic root of 212021109 is about 596.2929855749.

The spelling of 212021109 in words is "two hundred twelve million, twenty-one thousand, one hundred nine".