18672188537 has 4 divisors (see below), whose sum is σ = 18674746356. Its totient is φ = 18669630720.

The previous prime is 18672188503. The next prime is 18672188581. The reversal of 18672188537 is 73588127681.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3331136656 + 15341051881 = 57716^2 + 123859^2 .

It is a cyclic number.

It is not a de Polignac number, because 18672188537 - 2²⁰ = 18671139961 is a prime.

It is a super-2 number, since 2×18672188537² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18672184537) 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, 1267928 + ... + 1282569.

It is an arithmetic number, because the mean of its divisors is an integer number (4668686589).

Almost surely, 2^18672188537 is an apocalyptic number.

It is an amenable number.

18672188537 is a deficient number, since it is larger than the sum of its proper divisors (2557819).

18672188537 is an equidigital number, since it uses as much as digits as its factorization.

18672188537 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2557818.

The product of its digits is 4515840, while the sum is 56.

The spelling of 18672188537 in words is "eighteen billion, six hundred seventy-two million, one hundred eighty-eight thousand, five hundred thirty-seven".