212890621 has 2 divisors, whose sum is σ = 212890622. Its totient is φ = 212890620.

The previous prime is 212890591. The next prime is 212890631. The reversal of 212890621 is 126098212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 135256900 + 77633721 = 11630^2 + 8811^2 .

It is a cyclic number.

It is not a de Polignac number, because 212890621 - 2¹³ = 212882429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212890631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106445310 + 106445311.

It is an arithmetic number, because the mean of its divisors is an integer number (106445311).

Almost surely, 2^212890621 is an apocalyptic number.

It is an amenable number.

212890621 is a deficient number, since it is larger than the sum of its proper divisors (1).

212890621 is an equidigital number, since it uses as much as digits as its factorization.

212890621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 212890621 is about 14590.7717753380. The cubic root of 212890621 is about 597.1070188897.

The spelling of 212890621 in words is "two hundred twelve million, eight hundred ninety thousand, six hundred twenty-one".