1321373779 has 4 divisors (see below), whose sum is σ = 1441498680. Its totient is φ = 1201248880.

The previous prime is 1321373771. The next prime is 1321373783. The reversal of 1321373779 is 9773731231.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1321373779 - 2³ = 1321373771 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1321373771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 60062434 + ... + 60062455.

It is an arithmetic number, because the mean of its divisors is an integer number (360374670).

Almost surely, 2^1321373779 is an apocalyptic number.

1321373779 is a deficient number, since it is larger than the sum of its proper divisors (120124901).

1321373779 is a wasteful number, since it uses less digits than its factorization.

1321373779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120124900.

The product of its digits is 166698, while the sum is 43.

The square root of 1321373779 is about 36350.7053439132. The cubic root of 1321373779 is about 1097.3417296585.

The spelling of 1321373779 in words is "one billion, three hundred twenty-one million, three hundred seventy-three thousand, seven hundred seventy-nine".