321174066721561 has 4 divisors (see below), whose sum is σ = 321175620122112. Its totient is φ = 321172513321012.

The previous prime is 321174066721553. The next prime is 321174066721579. The reversal of 321174066721561 is 165127660471123.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 321174066721561 - 2³ = 321174066721553 is a prime.

It is a super-2 number, since 2×321174066721561² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 321174066721499 and 321174066721508.

It is not an unprimeable number, because it can be changed into a prime (321174066724561) 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, 776390101 + ... + 776803666.

It is an arithmetic number, because the mean of its divisors is an integer number (80293905030528).

Almost surely, 2^{321174066721561} is an apocalyptic number.

It is an amenable number.

321174066721561 is a deficient number, since it is larger than the sum of its proper divisors (1553400551).

321174066721561 is a wasteful number, since it uses less digits than its factorization.

321174066721561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1553400550.

The product of its (nonzero) digits is 2540160, while the sum is 52.

The spelling of 321174066721561 in words is "three hundred twenty-one trillion, one hundred seventy-four billion, sixty-six million, seven hundred twenty-one thousand, five hundred sixty-one".