17989791461 has 4 divisors (see below), whose sum is σ = 17990138124. Its totient is φ = 17989444800.

The previous prime is 17989791437. The next prime is 17989791509. The reversal of 17989791461 is 16419798971.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16419798971 = 92111 ⋅178261.

It can be written as a sum of positive squares in 2 ways, for example, as 8186811361 + 9802980100 = 90481^2 + 99010^2 .

It is a cyclic number.

It is not a de Polignac number, because 17989791461 - 2²⁶ = 17922682597 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 17989791394 and 17989791403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (17989791161) 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, 78020 + ... + 205101.

It is an arithmetic number, because the mean of its divisors is an integer number (4497534531).

Almost surely, 2^17989791461 is an apocalyptic number.

It is an amenable number.

17989791461 is a deficient number, since it is larger than the sum of its proper divisors (346663).

17989791461 is an equidigital number, since it uses as much as digits as its factorization.

17989791461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 346662.

The product of its digits is 6858432, while the sum is 62.

The spelling of 17989791461 in words is "seventeen billion, nine hundred eighty-nine million, seven hundred ninety-one thousand, four hundred sixty-one".