1691020799 has 4 divisors (see below), whose sum is σ = 1821099336. Its totient is φ = 1560942264.

The previous prime is 1691020783. The next prime is 1691020801. The reversal of 1691020799 is 9970201961.

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 1691020799 - 2⁴ = 1691020783 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1691020699) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 65039249 + ... + 65039274.

It is an arithmetic number, because the mean of its divisors is an integer number (455274834).

Almost surely, 2^1691020799 is an apocalyptic number.

1691020799 is a deficient number, since it is larger than the sum of its proper divisors (130078537).

1691020799 is a wasteful number, since it uses less digits than its factorization.

1691020799 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130078536.

The product of its (nonzero) digits is 61236, while the sum is 44.

The square root of 1691020799 is about 41122.0232843667. The cubic root of 1691020799 is about 1191.3782019582.

The spelling of 1691020799 in words is "one billion, six hundred ninety-one million, twenty thousand, seven hundred ninety-nine".