2157814636129 has 4 divisors (see below), whose sum is σ = 2157817588884. Its totient is φ = 2157811683376.

The previous prime is 2157814636127. The next prime is 2157814636139. The reversal of 2157814636129 is 9216364187512.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 1904463480529 + 253351155600 = 1380023^2 + 503340^2 .

It is a cyclic number.

It is not a de Polignac number, because 2157814636129 - 2¹ = 2157814636127 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 2157814636129.

It is not an unprimeable number, because it can be changed into a prime (2157814636127) 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, 516339 + ... + 2140615.

It is an arithmetic number, because the mean of its divisors is an integer number (539454397221).

Almost surely, 2^{2157814636129} is an apocalyptic number.

It is an amenable number.

2157814636129 is a deficient number, since it is larger than the sum of its proper divisors (2952755).

2157814636129 is a wasteful number, since it uses less digits than its factorization.

2157814636129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2952754.

The product of its digits is 4354560, while the sum is 55.

The spelling of 2157814636129 in words is "two trillion, one hundred fifty-seven billion, eight hundred fourteen million, six hundred thirty-six thousand, one hundred twenty-nine".