991593776943701 has 4 divisors (see below), whose sum is σ = 991660073259852. Its totient is φ = 991527480627552.

The previous prime is 991593776943667. The next prime is 991593776943709. The reversal of 991593776943701 is 107349677395199.

991593776943701 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 524404962012100 + 467188814931601 = 22899890^2 + 21614551^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-991593776943701 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 (991593776943709) 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, 33148135640 + ... + 33148165553.

It is an arithmetic number, because the mean of its divisors is an integer number (247915018314963).

Almost surely, 2^{991593776943701} is an apocalyptic number.

It is an amenable number.

991593776943701 is a deficient number, since it is larger than the sum of its proper divisors (66296316151).

991593776943701 is a wasteful number, since it uses less digits than its factorization.

991593776943701 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66296316150.

The product of its (nonzero) digits is 2430456840, while the sum is 80.

The spelling of 991593776943701 in words is "nine hundred ninety-one trillion, five hundred ninety-three billion, seven hundred seventy-six million, nine hundred forty-three thousand, seven hundred one".