635978209579 has 2 divisors, whose sum is σ = 635978209580. Its totient is φ = 635978209578.

The previous prime is 635978209577. The next prime is 635978209591. The reversal of 635978209579 is 975902879536.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 635978209579 - 2¹ = 635978209577 is a prime.

Together with 635978209577, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (635978209577) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 317989104789 + 317989104790.

It is an arithmetic number, because the mean of its divisors is an integer number (317989104790).

Almost surely, 2^635978209579 is an apocalyptic number.

635978209579 is a deficient number, since it is larger than the sum of its proper divisors (1).

635978209579 is an equidigital number, since it uses as much as digits as its factorization.

635978209579 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 257191200, while the sum is 70.

The spelling of 635978209579 in words is "six hundred thirty-five billion, nine hundred seventy-eight million, two hundred nine thousand, five hundred seventy-nine".