3991523122013 has 4 divisors (see below), whose sum is σ = 4561740710880. Its totient is φ = 3421305533148.

The previous prime is 3991523122009. The next prime is 3991523122051. The reversal of 3991523122013 is 3102213251993.

3991523122013 is digitally balanced in base 3, 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, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 3991523122013 - 2² = 3991523122009 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 (3991523124013) 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, 285108794423 + ... + 285108794436.

It is an arithmetic number, because the mean of its divisors is an integer number (1140435177720).

Almost surely, 2^{3991523122013} is an apocalyptic number.

It is an amenable number.

3991523122013 is a deficient number, since it is larger than the sum of its proper divisors (570217588867).

3991523122013 is an equidigital number, since it uses as much as digits as its factorization.

3991523122013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 570217588866.

The product of its (nonzero) digits is 87480, while the sum is 41.

The spelling of 3991523122013 in words is "three trillion, nine hundred ninety-one billion, five hundred twenty-three million, one hundred twenty-two thousand, thirteen".