217425997 has 8 divisors (see below), whose sum is σ = 218622456. Its totient is φ = 216233472.

The previous prime is 217425983. The next prime is 217426043. The reversal of 217425997 is 799524712.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 66357316 + 151068681 = 8146^2 + 12291^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-217425997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217425097) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 227673 + ... + 228625.

It is an arithmetic number, because the mean of its divisors is an integer number (27327807).

Almost surely, 2^217425997 is an apocalyptic number.

It is an amenable number.

217425997 is a deficient number, since it is larger than the sum of its proper divisors (1196459).

217425997 is an equidigital number, since it uses as much as digits as its factorization.

217425997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1967.

The product of its digits is 317520, while the sum is 46.

The square root of 217425997 is about 14745.3720536309. The cubic root of 217425997 is about 601.3174725852.

The spelling of 217425997 in words is "two hundred seventeen million, four hundred twenty-five thousand, nine hundred ninety-seven".