217317740 has 12 divisors (see below), whose sum is σ = 456367296. Its totient is φ = 86927088.

The previous prime is 217317697. The next prime is 217317767. The reversal of 217317740 is 47713712.

It is a junction number, because it is equal to n+sod(n) for n = 217317697 and 217317706.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5432924 + ... + 5432963.

It is an arithmetic number, because the mean of its divisors is an integer number (38030608).

Almost surely, 2^217317740 is an apocalyptic number.

217317740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

217317740 is an abundant number, since it is smaller than the sum of its proper divisors (239049556).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

217317740 is a wasteful number, since it uses less digits than its factorization.

217317740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10865896 (or 10865894 counting only the distinct ones).

The product of its (nonzero) digits is 8232, while the sum is 32.

The square root of 217317740 is about 14741.7007159961. The cubic root of 217317740 is about 601.2176568111.

The spelling of 217317740 in words is "two hundred seventeen million, three hundred seventeen thousand, seven hundred forty".