209290157 has 2 divisors, whose sum is σ = 209290158. Its totient is φ = 209290156.

The previous prime is 209290139. The next prime is 209290171. The reversal of 209290157 is 751092902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 208196041 + 1094116 = 14429^2 + 1046^2 .

It is a cyclic number.

It is not a de Polignac number, because 209290157 - 2¹⁸ = 209028013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (209290127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104645078 + 104645079.

It is an arithmetic number, because the mean of its divisors is an integer number (104645079).

Almost surely, 2^209290157 is an apocalyptic number.

It is an amenable number.

209290157 is a deficient number, since it is larger than the sum of its proper divisors (1).

209290157 is an equidigital number, since it uses as much as digits as its factorization.

209290157 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11340, while the sum is 35.

The square root of 209290157 is about 14466.8641038754. The cubic root of 209290157 is about 593.7217168134.

The spelling of 209290157 in words is "two hundred nine million, two hundred ninety thousand, one hundred fifty-seven".