213678917 has 2 divisors, whose sum is σ = 213678918. Its totient is φ = 213678916.

The previous prime is 213678889. The next prime is 213678937. The reversal of 213678917 is 719876312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 213422881 + 256036 = 14609^2 + 506^2 .

It is a cyclic number.

It is not a de Polignac number, because 213678917 - 2⁶ = 213678853 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (213678937) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106839458 + 106839459.

It is an arithmetic number, because the mean of its divisors is an integer number (106839459).

Almost surely, 2^213678917 is an apocalyptic number.

It is an amenable number.

213678917 is a deficient number, since it is larger than the sum of its proper divisors (1).

213678917 is an equidigital number, since it uses as much as digits as its factorization.

213678917 is an evil number, because the sum of its binary digits is even.

The product of its digits is 127008, while the sum is 44.

The square root of 213678917 is about 14617.7603277657. The cubic root of 213678917 is about 597.8431047029.

The spelling of 213678917 in words is "two hundred thirteen million, six hundred seventy-eight thousand, nine hundred seventeen".