3991626949481 has 4 divisors (see below), whose sum is σ = 4059281643600. Its totient is φ = 3923972255364.

The previous prime is 3991626949477. The next prime is 3991626949483. The reversal of 3991626949481 is 1849496261993.

3991626949481 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, 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 3991626949481 - 2² = 3991626949477 is a prime.

It is a super-2 number, since 2×3991626949481² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3991626949483) 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, 33827346971 + ... + 33827347088.

It is an arithmetic number, because the mean of its divisors is an integer number (1014820410900).

Almost surely, 2^{3991626949481} is an apocalyptic number.

It is an amenable number.

3991626949481 is a deficient number, since it is larger than the sum of its proper divisors (67654694119).

3991626949481 is an equidigital number, since it uses as much as digits as its factorization.

3991626949481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67654694118.

The product of its digits is 181398528, while the sum is 71.

The spelling of 3991626949481 in words is "three trillion, nine hundred ninety-one billion, six hundred twenty-six million, nine hundred forty-nine thousand, four hundred eighty-one".