1321664439 has 16 divisors (see below), whose sum is σ = 1868836320. Its totient is φ = 827965440.

The previous prime is 1321664431. The next prime is 1321664441. The reversal of 1321664439 is 9344661231.

It is not a de Polignac number, because 1321664439 - 2³ = 1321664431 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1321664397 and 1321664406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321664431) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12477 + ... + 52905.

It is an arithmetic number, because the mean of its divisors is an integer number (116802270).

Almost surely, 2^1321664439 is an apocalyptic number.

1321664439 is a deficient number, since it is larger than the sum of its proper divisors (547171881).

1321664439 is a wasteful number, since it uses less digits than its factorization.

1321664439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41090.

The product of its digits is 93312, while the sum is 39.

The square root of 1321664439 is about 36354.7031207793. The cubic root of 1321664439 is about 1097.4221837961.

The spelling of 1321664439 in words is "one billion, three hundred twenty-one million, six hundred sixty-four thousand, four hundred thirty-nine".