2121199966 has 4 divisors (see below), whose sum is σ = 3181799952. Its totient is φ = 1060599982.

The previous prime is 2121199963. The next prime is 2121199979. The reversal of 2121199966 is 6699911212.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121199963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 530299990 + ... + 530299993.

It is an arithmetic number, because the mean of its divisors is an integer number (795449988).

Almost surely, 2^2121199966 is an apocalyptic number.

2121199966 is a deficient number, since it is larger than the sum of its proper divisors (1060599986).

2121199966 is a wasteful number, since it uses less digits than its factorization.

2121199966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1060599985.

The product of its digits is 104976, while the sum is 46.

The square root of 2121199966 is about 46056.4866875449. The cubic root of 2121199966 is about 1284.8739884609.

The spelling of 2121199966 in words is "two billion, one hundred twenty-one million, one hundred ninety-nine thousand, nine hundred sixty-six".