15964321 has 2 divisors, whose sum is σ = 15964322. Its totient is φ = 15964320.

The previous prime is 15964283. The next prime is 15964327. The reversal of 15964321 is 12346951.

15964321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9000000 + 6964321 = 3000^2 + 2639^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15964321 is a prime.

It is not a weakly prime, because it can be changed into another prime (15964327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7982160 + 7982161.

It is an arithmetic number, because the mean of its divisors is an integer number (7982161).

Almost surely, 2^15964321 is an apocalyptic number.

It is an amenable number.

15964321 is a deficient number, since it is larger than the sum of its proper divisors (1).

15964321 is an equidigital number, since it uses as much as digits as its factorization.

15964321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6480, while the sum is 31.

The square root of 15964321 is about 3995.5376359133. The cubic root of 15964321 is about 251.7967675685.

The spelling of 15964321 in words is "fifteen million, nine hundred sixty-four thousand, three hundred twenty-one".