20135128879 has 2 divisors, whose sum is σ = 20135128880. Its totient is φ = 20135128878.

The previous prime is 20135128847. The next prime is 20135128907. The reversal of 20135128879 is 97882153102.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20135128879 - 2⁵ = 20135128847 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20135122879) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10067564439 + 10067564440.

It is an arithmetic number, because the mean of its divisors is an integer number (10067564440).

Almost surely, 2^20135128879 is an apocalyptic number.

20135128879 is a deficient number, since it is larger than the sum of its proper divisors (1).

20135128879 is an equidigital number, since it uses as much as digits as its factorization.

20135128879 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 241920, while the sum is 46.

The spelling of 20135128879 in words is "twenty billion, one hundred thirty-five million, one hundred twenty-eight thousand, eight hundred seventy-nine".