212123999999 has 4 divisors (see below), whose sum is σ = 212125404336. Its totient is φ = 212122595664.

The previous prime is 212123999959. The next prime is 212124000013. The reversal of 212123999999 is 999999321212.

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

It is a cyclic number.

It is not a de Polignac number, because 212123999999 - 2²⁰ = 212122951423 is a prime.

It is a Duffinian number.

212123999999 is a modest number, since divided by 999999 gives 212123 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212123999929) 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, 443939 + ... + 788244.

It is an arithmetic number, because the mean of its divisors is an integer number (53031351084).

Almost surely, 2^212123999999 is an apocalyptic number.

212123999999 is a deficient number, since it is larger than the sum of its proper divisors (1404337).

212123999999 is a wasteful number, since it uses less digits than its factorization.

212123999999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1404336.

The product of its digits is 12754584, while the sum is 65.

The spelling of 212123999999 in words is "two hundred twelve billion, one hundred twenty-three million, nine hundred ninety-nine thousand, nine hundred ninety-nine".