2135243669891 has 4 divisors (see below), whose sum is σ = 2204122497984. Its totient is φ = 2066364841800.

The previous prime is 2135243669887. The next prime is 2135243669917. The reversal of 2135243669891 is 1989663425312.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2135243669891 - 2² = 2135243669887 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2135243669891.

It is not an unprimeable number, because it can be changed into a prime (2135243669861) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34439414000 + ... + 34439414061.

It is an arithmetic number, because the mean of its divisors is an integer number (551030624496).

Almost surely, 2^{2135243669891} is an apocalyptic number.

2135243669891 is a deficient number, since it is larger than the sum of its proper divisors (68878828093).

2135243669891 is an equidigital number, since it uses as much as digits as its factorization.

2135243669891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68878828092.

The product of its digits is 16796160, while the sum is 59.

The spelling of 2135243669891 in words is "two trillion, one hundred thirty-five billion, two hundred forty-three million, six hundred sixty-nine thousand, eight hundred ninety-one".