2661320321 has 8 divisors (see below), whose sum is σ = 2940009600. Its totient is φ = 2388756240.

The previous prime is 2661320297. The next prime is 2661320351. The reversal of 2661320321 is 1230231662.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2661320321 - 2¹⁴ = 2661303937 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2661320351) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1530386 + ... + 1532123.

It is an arithmetic number, because the mean of its divisors is an integer number (367501200).

Almost surely, 2^2661320321 is an apocalyptic number.

It is an amenable number.

2661320321 is a deficient number, since it is larger than the sum of its proper divisors (278689279).

2661320321 is a wasteful number, since it uses less digits than its factorization.

2661320321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3062599.

The product of its (nonzero) digits is 2592, while the sum is 26.

The square root of 2661320321 is about 51587.9862080310. The cubic root of 2661320321 is about 1385.7951914172.

Adding to 2661320321 its reverse (1230231662), we get a palindrome (3891551983).

The spelling of 2661320321 in words is "two billion, six hundred sixty-one million, three hundred twenty thousand, three hundred twenty-one".