3144781391321 has 4 divisors (see below), whose sum is σ = 3172611315252. Its totient is φ = 3116951467392.

The previous prime is 3144781391291. The next prime is 3144781391371. The reversal of 3144781391321 is 1231931874413.

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 463031255296 + 2681750136025 = 680464^2 + 1637605^2 .

It is a cyclic number.

It is not a de Polignac number, because 3144781391321 - 2¹⁰ = 3144781390297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3144781391371) 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, 13914961796 + ... + 13914962021.

It is an arithmetic number, because the mean of its divisors is an integer number (793152828813).

Almost surely, 2^{3144781391321} is an apocalyptic number.

It is an amenable number.

3144781391321 is a deficient number, since it is larger than the sum of its proper divisors (27829923931).

3144781391321 is a wasteful number, since it uses less digits than its factorization.

3144781391321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27829923930.

The product of its digits is 435456, while the sum is 47.

The spelling of 3144781391321 in words is "three trillion, one hundred forty-four billion, seven hundred eighty-one million, three hundred ninety-one thousand, three hundred twenty-one".