212099999 has 4 divisors (see below), whose sum is σ = 212183664. Its totient is φ = 212016336.

The previous prime is 212099981. The next prime is 212100017. The reversal of 212099999 is 999990212.

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

It is an interprime number because it is at equal distance from previous prime (212099981) and next prime (212100017).

It is a cyclic number.

It is not a de Polignac number, because 212099999 - 2⁸ = 212099743 is a prime.

It is a Duffinian number.

212099999 is a modest number, since divided by 99999 gives 2120 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212090999) 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, 37907 + ... + 43140.

It is an arithmetic number, because the mean of its divisors is an integer number (53045916).

Almost surely, 2^212099999 is an apocalyptic number.

212099999 is a deficient number, since it is larger than the sum of its proper divisors (83665).

212099999 is an equidigital number, since it uses as much as digits as its factorization.

212099999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83664.

The product of its (nonzero) digits is 236196, while the sum is 50.

The square root of 212099999 is about 14563.6533534687. The cubic root of 212099999 is about 596.3669337470.

The spelling of 212099999 in words is "two hundred twelve million, ninety-nine thousand, nine hundred ninety-nine".