1321564321 has 8 divisors (see below), whose sum is σ = 1647664704. Its totient is φ = 1029790320.

The previous prime is 1321564319. The next prime is 1321564327. The reversal of 1321564321 is 1234651231.

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 1321564321 - 2¹ = 1321564319 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1321564321.

It is not an unprimeable number, because it can be changed into a prime (1321564327) 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, 8581510 + ... + 8581663.

It is an arithmetic number, because the mean of its divisors is an integer number (205958088).

Almost surely, 2^1321564321 is an apocalyptic number.

1321564321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1321564321 is a deficient number, since it is larger than the sum of its proper divisors (326100383).

1321564321 is a wasteful number, since it uses less digits than its factorization.

1321564321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17163191.

The product of its digits is 4320, while the sum is 28.

The square root of 1321564321 is about 36353.3261339317. The cubic root of 1321564321 is about 1097.3944726552.

The spelling of 1321564321 in words is "one billion, three hundred twenty-one million, five hundred sixty-four thousand, three hundred twenty-one".