212706021 has 24 divisors (see below), whose sum is σ = 314816320. Its totient is φ = 127638720.

The previous prime is 212706017. The next prime is 212706029. The reversal of 212706021 is 120607212.

It is not a de Polignac number, because 212706021 - 2² = 212706017 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212706029) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 34545 + ... + 40233.

Almost surely, 2^212706021 is an apocalyptic number.

It is an amenable number.

212706021 is a deficient number, since it is larger than the sum of its proper divisors (102110299).

212706021 is a wasteful number, since it uses less digits than its factorization.

212706021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5817 (or 5806 counting only the distinct ones).

The product of its (nonzero) digits is 336, while the sum is 21.

The square root of 212706021 is about 14584.4444871925. Note that the first 4 decimals coincide. The cubic root of 212706021 is about 596.9343827727.

The spelling of 212706021 in words is "two hundred twelve million, seven hundred six thousand, twenty-one".