2121923205 has 12 divisors (see below), whose sum is σ = 3678000300. Its totient is φ = 1131692352.

The previous prime is 2121923191. The next prime is 2121923207. The reversal of 2121923205 is 5023291212.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1619177121 + 502746084 = 40239^2 + 22422^2 .

It is not a de Polignac number, because 2121923205 - 2⁷ = 2121923077 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121923207) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 23576880 + ... + 23576969.

It is an arithmetic number, because the mean of its divisors is an integer number (306500025).

Almost surely, 2^2121923205 is an apocalyptic number.

It is an amenable number.

2121923205 is a deficient number, since it is larger than the sum of its proper divisors (1556077095).

2121923205 is a wasteful number, since it uses less digits than its factorization.

2121923205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47153860 (or 47153857 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 2121923205 is about 46064.3376702629. The cubic root of 2121923205 is about 1285.0200010008.

The spelling of 2121923205 in words is "two billion, one hundred twenty-one million, nine hundred twenty-three thousand, two hundred five".