1321917399 has 48 divisors (see below), whose sum is σ = 2217196800. Its totient is φ = 750055680.

The previous prime is 1321917371. The next prime is 1321917413. The reversal of 1321917399 is 9937191231.

It is not a de Polignac number, because 1321917399 - 2⁷ = 1321917271 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321917329) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 332944 + ... + 336890.

It is an arithmetic number, because the mean of its divisors is an integer number (46191600).

Almost surely, 2^1321917399 is an apocalyptic number.

1321917399 is a deficient number, since it is larger than the sum of its proper divisors (895279401).

1321917399 is a wasteful number, since it uses less digits than its factorization.

1321917399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4180 (or 4177 counting only the distinct ones).

The product of its digits is 91854, while the sum is 45.

The square root of 1321917399 is about 36358.1820090059. The cubic root of 1321917399 is about 1097.4921930457.

The spelling of 1321917399 in words is "one billion, three hundred twenty-one million, nine hundred seventeen thousand, three hundred ninety-nine".