209019157 has 2 divisors, whose sum is σ = 209019158. Its totient is φ = 209019156.

The previous prime is 209019127. The next prime is 209019169. The reversal of 209019157 is 751910902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 176597521 + 32421636 = 13289^2 + 5694^2 .

It is a cyclic number.

It is not a de Polignac number, because 209019157 - 2²⁷ = 74801429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (209019127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104509578 + 104509579.

It is an arithmetic number, because the mean of its divisors is an integer number (104509579).

Almost surely, 2^209019157 is an apocalyptic number.

It is an amenable number.

209019157 is a deficient number, since it is larger than the sum of its proper divisors (1).

209019157 is an equidigital number, since it uses as much as digits as its factorization.

209019157 is an odious number, because the sum of its binary digits is odd.

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

The square root of 209019157 is about 14457.4948383183. The cubic root of 209019157 is about 593.4653453334.

The spelling of 209019157 in words is "two hundred nine million, nineteen thousand, one hundred fifty-seven".