217707457 has 12 divisors (see below), whose sum is σ = 252295056. Its totient is φ = 186271040.

The previous prime is 217707449. The next prime is 217707473. The reversal of 217707457 is 754707712.

It is not a de Polignac number, because 217707457 - 2³ = 217707449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (217707407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 31063 + ... + 37420.

It is an arithmetic number, because the mean of its divisors is an integer number (21024588).

Almost surely, 2^217707457 is an apocalyptic number.

It is an amenable number.

217707457 is a deficient number, since it is larger than the sum of its proper divisors (34587599).

217707457 is a wasteful number, since it uses less digits than its factorization.

217707457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68528 (or 68511 counting only the distinct ones).

The product of its (nonzero) digits is 96040, while the sum is 40.

The square root of 217707457 is about 14754.9129783947. The cubic root of 217707457 is about 601.5768310797.

The spelling of 217707457 in words is "two hundred seventeen million, seven hundred seven thousand, four hundred fifty-seven".