209973947 has 2 divisors, whose sum is σ = 209973948. Its totient is φ = 209973946.

The previous prime is 209973917. The next prime is 209973977. The reversal of 209973947 is 749379902.

It is a balanced prime because it is at equal distance from previous prime (209973917) and next prime (209973977).

It is a cyclic number.

It is not a de Polignac number, because 209973947 - 2⁸ = 209973691 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 209973895 and 209973904.

It is not a weakly prime, because it can be changed into another prime (209973917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104986973 + 104986974.

It is an arithmetic number, because the mean of its divisors is an integer number (104986974).

Almost surely, 2^209973947 is an apocalyptic number.

209973947 is a deficient number, since it is larger than the sum of its proper divisors (1).

209973947 is an equidigital number, since it uses as much as digits as its factorization.

209973947 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 857304, while the sum is 50.

The square root of 209973947 is about 14490.4778044066. The cubic root of 209973947 is about 594.3676137838.

The spelling of 209973947 in words is "two hundred nine million, nine hundred seventy-three thousand, nine hundred forty-seven".