212120999929 has 2 divisors, whose sum is σ = 212120999930. Its totient is φ = 212120999928.

The previous prime is 212120999897. The next prime is 212121000029. The reversal of 212120999929 is 929999021212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 171001271529 + 41119728400 = 413523^2 + 202780^2 .

It is a cyclic number.

It is not a de Polignac number, because 212120999929 - 2⁵ = 212120999897 is a prime.

It is a super-3 number, since 3×212120999929³ (a number of 35 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a self number, because there is not a number n which added to its sum of digits gives 212120999929.

It is not a weakly prime, because it can be changed into another prime (212120999729) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106060499964 + 106060499965.

It is an arithmetic number, because the mean of its divisors is an integer number (106060499965).

Almost surely, 2^212120999929 is an apocalyptic number.

It is an amenable number.

212120999929 is a deficient number, since it is larger than the sum of its proper divisors (1).

212120999929 is an equidigital number, since it uses as much as digits as its factorization.

212120999929 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 944784, while the sum is 55.

The spelling of 212120999929 in words is "two hundred twelve billion, one hundred twenty million, nine hundred ninety-nine thousand, nine hundred twenty-nine".