209719051 has 2 divisors, whose sum is σ = 209719052. Its totient is φ = 209719050.

The previous prime is 209719049. The next prime is 209719063. The reversal of 209719051 is 150917902.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 209719051 - 2¹ = 209719049 is a prime.

Together with 209719049, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 209718998 and 209719016.

It is not a weakly prime, because it can be changed into another prime (209719001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104859525 + 104859526.

It is an arithmetic number, because the mean of its divisors is an integer number (104859526).

Almost surely, 2^209719051 is an apocalyptic number.

209719051 is a deficient number, since it is larger than the sum of its proper divisors (1).

209719051 is an equidigital number, since it uses as much as digits as its factorization.

209719051 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5670, while the sum is 34.

The square root of 209719051 is about 14481.6798404053. The cubic root of 209719051 is about 594.1270073091.

The spelling of 209719051 in words is "two hundred nine million, seven hundred nineteen thousand, fifty-one".