16939842581 has 4 divisors (see below), whose sum is σ = 16941749952. Its totient is φ = 16937935212.

The previous prime is 16939842541. The next prime is 16939842589. The reversal of 16939842581 is 18524893961.

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 16939842581 - 2¹⁰ = 16939841557 is a prime.

It is a super-2 number, since 2×16939842581² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16939842589) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 940301 + ... + 958146.

It is an arithmetic number, because the mean of its divisors is an integer number (4235437488).

Almost surely, 2^16939842581 is an apocalyptic number.

It is an amenable number.

16939842581 is a deficient number, since it is larger than the sum of its proper divisors (1907371).

16939842581 is an equidigital number, since it uses as much as digits as its factorization.

16939842581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1907370.

The product of its digits is 3732480, while the sum is 56.

The spelling of 16939842581 in words is "sixteen billion, nine hundred thirty-nine million, eight hundred forty-two thousand, five hundred eighty-one".