217263993 has 16 divisors (see below), whose sum is σ = 312026880. Its totient is φ = 134026704.

The previous prime is 217263989. The next prime is 217264001. The reversal of 217263993 is 399362712.

It is not a de Polignac number, because 217263993 - 2² = 217263989 is a prime.

It is not an unprimeable number, because it can be changed into a prime (217263973) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 41871 + ... + 46772.

It is an arithmetic number, because the mean of its divisors is an integer number (19501680).

Almost surely, 2^217263993 is an apocalyptic number.

It is an amenable number.

217263993 is a deficient number, since it is larger than the sum of its proper divisors (94762887).

217263993 is a wasteful number, since it uses less digits than its factorization.

217263993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88708.

The product of its digits is 122472, while the sum is 42.

The square root of 217263993 is about 14739.8776453538. The cubic root of 217263993 is about 601.1680883625.

The spelling of 217263993 in words is "two hundred seventeen million, two hundred sixty-three thousand, nine hundred ninety-three".