6427989817 has 2 divisors, whose sum is σ = 6427989818. Its totient is φ = 6427989816.

The previous prime is 6427989767. The next prime is 6427989823. The reversal of 6427989817 is 7189897246.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5994475776 + 433514041 = 77424^2 + 20821^2 .

It is a cyclic number.

It is not a de Polignac number, because 6427989817 - 2¹⁵ = 6427957049 is a prime.

It is not a weakly prime, because it can be changed into another prime (6421989817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3213994908 + 3213994909.

It is an arithmetic number, because the mean of its divisors is an integer number (3213994909).

Almost surely, 2^6427989817 is an apocalyptic number.

It is an amenable number.

6427989817 is a deficient number, since it is larger than the sum of its proper divisors (1).

6427989817 is an equidigital number, since it uses as much as digits as its factorization.

6427989817 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12192768, while the sum is 61.

The square root of 6427989817 is about 80174.7455063002. The cubic root of 6427989817 is about 1859.3382060942.

The spelling of 6427989817 in words is "six billion, four hundred twenty-seven million, nine hundred eighty-nine thousand, eight hundred seventeen".