517219991 has 2 divisors, whose sum is σ = 517219992. Its totient is φ = 517219990.

The previous prime is 517219979. The next prime is 517220009. The reversal of 517219991 is 199912715.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-517219991 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 (517219921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 258609995 + 258609996.

It is an arithmetic number, because the mean of its divisors is an integer number (258609996).

Almost surely, 2^517219991 is an apocalyptic number.

517219991 is a deficient number, since it is larger than the sum of its proper divisors (1).

517219991 is an equidigital number, since it uses as much as digits as its factorization.

517219991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51030, while the sum is 44.

The square root of 517219991 is about 22742.4710838554. The cubic root of 517219991 is about 802.7095578222.

The spelling of 517219991 in words is "five hundred seventeen million, two hundred nineteen thousand, nine hundred ninety-one".