212708921 has 2 divisors, whose sum is σ = 212708922. Its totient is φ = 212708920.

The previous prime is 212708897. The next prime is 212708957. The reversal of 212708921 is 129807212.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 211411600 + 1297321 = 14540^2 + 1139^2 .

It is a cyclic number.

It is not a de Polignac number, because 212708921 - 2¹⁴ = 212692537 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (212708521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106354460 + 106354461.

It is an arithmetic number, because the mean of its divisors is an integer number (106354461).

Almost surely, 2^212708921 is an apocalyptic number.

It is an amenable number.

212708921 is a deficient number, since it is larger than the sum of its proper divisors (1).

212708921 is an equidigital number, since it uses as much as digits as its factorization.

212708921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4032, while the sum is 32.

The square root of 212708921 is about 14584.5439078498. The cubic root of 212708921 is about 596.9370955965.

The spelling of 212708921 in words is "two hundred twelve million, seven hundred eight thousand, nine hundred twenty-one".