1329690921791 has 4 divisors (see below), whose sum is σ = 1332761801952. Its totient is φ = 1326620041632.

The previous prime is 1329690921773. The next prime is 1329690921809. The reversal of 1329690921791 is 1971290969231.

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

It is an interprime number because it is at equal distance from previous prime (1329690921773) and next prime (1329690921809).

It is a cyclic number.

It is not a de Polignac number, because 1329690921791 - 2¹⁴ = 1329690905407 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1329690921791.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1329690921991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1535439431 + ... + 1535440296.

It is an arithmetic number, because the mean of its divisors is an integer number (333190450488).

Almost surely, 2^{1329690921791} is an apocalyptic number.

1329690921791 is a deficient number, since it is larger than the sum of its proper divisors (3070880161).

1329690921791 is an equidigital number, since it uses as much as digits as its factorization.

1329690921791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3070880160.

The product of its (nonzero) digits is 3306744, while the sum is 59.

The spelling of 1329690921791 in words is "one trillion, three hundred twenty-nine billion, six hundred ninety million, nine hundred twenty-one thousand, seven hundred ninety-one".