206919997 has 2 divisors, whose sum is σ = 206919998. Its totient is φ = 206919996.

The previous prime is 206919961. The next prime is 206920027. The reversal of 206919997 is 799919602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 183358681 + 23561316 = 13541^2 + 4854^2 .

It is a cyclic number.

It is not a de Polignac number, because 206919997 - 2²⁷ = 72702269 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206919697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103459998 + 103459999.

It is an arithmetic number, because the mean of its divisors is an integer number (103459999).

Almost surely, 2^206919997 is an apocalyptic number.

It is an amenable number.

206919997 is a deficient number, since it is larger than the sum of its proper divisors (1).

206919997 is an equidigital number, since it uses as much as digits as its factorization.

206919997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 551124, while the sum is 52.

The square root of 206919997 is about 14384.7140048038. The cubic root of 206919997 is about 591.4719514089.

The spelling of 206919997 in words is "two hundred six million, nine hundred nineteen thousand, nine hundred ninety-seven".