209734157 has 2 divisors, whose sum is σ = 209734158. Its totient is φ = 209734156.

The previous prime is 209734139. The next prime is 209734169. The reversal of 209734157 is 751437902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 181548676 + 28185481 = 13474^2 + 5309^2 .

It is a cyclic number.

It is not a de Polignac number, because 209734157 - 2¹⁴ = 209717773 is a prime.

It is a super-2 number, since 2×209734157² = 87976833225001298, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 209734157.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (209794157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104867078 + 104867079.

It is an arithmetic number, because the mean of its divisors is an integer number (104867079).

Almost surely, 2^209734157 is an apocalyptic number.

It is an amenable number.

209734157 is a deficient number, since it is larger than the sum of its proper divisors (1).

209734157 is an equidigital number, since it uses as much as digits as its factorization.

209734157 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 52920, while the sum is 38.

The square root of 209734157 is about 14482.2013865296. The cubic root of 209734157 is about 594.1412718964.

The spelling of 209734157 in words is "two hundred nine million, seven hundred thirty-four thousand, one hundred fifty-seven".