18036523661 has 8 divisors (see below), whose sum is σ = 20446261920. Its totient is φ = 15772830192.

The previous prime is 18036523621. The next prime is 18036523723. The reversal of 18036523661 is 16632563081.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18036523661 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 (18036523621) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36510935 + ... + 36511428.

It is an arithmetic number, because the mean of its divisors is an integer number (2555782740).

Almost surely, 2^18036523661 is an apocalyptic number.

It is an amenable number.

18036523661 is a deficient number, since it is larger than the sum of its proper divisors (2409738259).

18036523661 is a wasteful number, since it uses less digits than its factorization.

18036523661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73022395.

The product of its (nonzero) digits is 155520, while the sum is 41.

The spelling of 18036523661 in words is "eighteen billion, thirty-six million, five hundred twenty-three thousand, six hundred sixty-one".