206019421 has 2 divisors, whose sum is σ = 206019422. Its totient is φ = 206019420.

The previous prime is 206019409. The next prime is 206019431. The reversal of 206019421 is 124910602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 154107396 + 51912025 = 12414^2 + 7205^2 .

It is a cyclic number.

It is not a de Polignac number, because 206019421 - 2⁹ = 206018909 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206019431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103009710 + 103009711.

It is an arithmetic number, because the mean of its divisors is an integer number (103009711).

Almost surely, 2^206019421 is an apocalyptic number.

It is an amenable number.

206019421 is a deficient number, since it is larger than the sum of its proper divisors (1).

206019421 is an equidigital number, since it uses as much as digits as its factorization.

206019421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 206019421 is about 14353.3766410556. The cubic root of 206019421 is about 590.6126175320.

The spelling of 206019421 in words is "two hundred six million, nineteen thousand, four hundred twenty-one".