3156646313921 has 4 divisors (see below), whose sum is σ = 3158183893332. Its totient is φ = 3155108734512.

The previous prime is 3156646313911. The next prime is 3156646314023. The reversal of 3156646313921 is 1293136466513.

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 755265283600 + 2401381030321 = 869060^2 + 1549639^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3156646313921 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 3156646313921.

It is not an unprimeable number, because it can be changed into a prime (3156646313911) 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, 768786626 + ... + 768790731.

It is an arithmetic number, because the mean of its divisors is an integer number (789545973333).

Almost surely, 2^{3156646313921} is an apocalyptic number.

It is an amenable number.

3156646313921 is a deficient number, since it is larger than the sum of its proper divisors (1537579411).

3156646313921 is a wasteful number, since it uses less digits than its factorization.

3156646313921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1537579410.

The product of its digits is 2099520, while the sum is 50.

The spelling of 3156646313921 in words is "three trillion, one hundred fifty-six billion, six hundred forty-six million, three hundred thirteen thousand, nine hundred twenty-one".