212666811 has 12 divisors (see below), whose sum is σ = 329850792. Its totient is φ = 121523808.

The previous prime is 212666767. The next prime is 212666813. The reversal of 212666811 is 118666212.

It is not a de Polignac number, because 212666811 - 2⁹ = 212666299 is a prime.

It is not an unprimeable number, because it can be changed into a prime (212666813) 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, 723210 + ... + 723503.

It is an arithmetic number, because the mean of its divisors is an integer number (27487566).

Almost surely, 2^212666811 is an apocalyptic number.

212666811 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

212666811 is a deficient number, since it is larger than the sum of its proper divisors (117183981).

212666811 is a wasteful number, since it uses less digits than its factorization.

212666811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1446730 (or 1446723 counting only the distinct ones).

The product of its digits is 6912, while the sum is 33.

The square root of 212666811 is about 14583.1001848030. The cubic root of 212666811 is about 596.8977011038.

The spelling of 212666811 in words is "two hundred twelve million, six hundred sixty-six thousand, eight hundred eleven".