217013931 has 16 divisors (see below), whose sum is σ = 332589600. Its totient is φ = 139686624.

The previous prime is 217013921. The next prime is 217013933. The reversal of 217013931 is 139310712.

It is not a de Polignac number, because 217013931 - 2⁷ = 217013803 is a prime.

It is a super-2 number, since 2×217013931² = 94190092496145522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 217013895 and 217013904.

It is not an unprimeable number, because it can be changed into a prime (217013933) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 137796 + ... + 139361.

It is an arithmetic number, because the mean of its divisors is an integer number (20786850).

Almost surely, 2^217013931 is an apocalyptic number.

217013931 is a deficient number, since it is larger than the sum of its proper divisors (115575669).

217013931 is a wasteful number, since it uses less digits than its factorization.

217013931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 277195 (or 277189 counting only the distinct ones).

The product of its (nonzero) digits is 1134, while the sum is 27.

The square root of 217013931 is about 14731.3927040182. The cubic root of 217013931 is about 600.9373598316.

The spelling of 217013931 in words is "two hundred seventeen million, thirteen thousand, nine hundred thirty-one".