217289157 has 4 divisors (see below), whose sum is σ = 289718880. Its totient is φ = 144859436.

The previous prime is 217289147. The next prime is 217289161. The reversal of 217289157 is 751982712.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 217289157 - 2¹⁰ = 217288133 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217289147) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36214857 + ... + 36214862.

It is an arithmetic number, because the mean of its divisors is an integer number (72429720).

Almost surely, 2^217289157 is an apocalyptic number.

It is an amenable number.

217289157 is a deficient number, since it is larger than the sum of its proper divisors (72429723).

217289157 is an equidigital number, since it uses as much as digits as its factorization.

217289157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72429722.

The product of its digits is 70560, while the sum is 42.

The square root of 217289157 is about 14740.7312233824. The cubic root of 217289157 is about 601.1912970092.

The spelling of 217289157 in words is "two hundred seventeen million, two hundred eighty-nine thousand, one hundred fifty-seven".