2127281945821 has 4 divisors (see below), whose sum is σ = 2127562708572. Its totient is φ = 2127001183072.

The previous prime is 2127281945753. The next prime is 2127281945827. The reversal of 2127281945821 is 1285491827212.

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

It can be written as a sum of positive squares in 2 ways, for example, as 334909893796 + 1792372052025 = 578714^2 + 1338795^2 .

It is a cyclic number.

It is not a de Polignac number, because 2127281945821 - 2²⁷ = 2127147728093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2127281945827) 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, 140370010 + ... + 140385163.

It is an arithmetic number, because the mean of its divisors is an integer number (531890677143).

Almost surely, 2^{2127281945821} is an apocalyptic number.

It is an amenable number.

2127281945821 is a deficient number, since it is larger than the sum of its proper divisors (280762751).

2127281945821 is an equidigital number, since it uses as much as digits as its factorization.

2127281945821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 280762750.

The product of its digits is 1290240, while the sum is 52.

The spelling of 2127281945821 in words is "two trillion, one hundred twenty-seven billion, two hundred eighty-one million, nine hundred forty-five thousand, eight hundred twenty-one".