18200658821 has 4 divisors (see below), whose sum is σ = 18544067532. Its totient is φ = 17857250112.

The previous prime is 18200658743. The next prime is 18200658829. The reversal of 18200658821 is 12885600281.

It is a happy number.

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 10203828196 + 7996830625 = 101014^2 + 89425^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18200658821 is a prime.

It is a super-2 number, since 2×18200658821² (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 (18200658829) 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, 171704276 + ... + 171704381.

It is an arithmetic number, because the mean of its divisors is an integer number (4636016883).

Almost surely, 2^18200658821 is an apocalyptic number.

It is an amenable number.

18200658821 is a deficient number, since it is larger than the sum of its proper divisors (343408711).

18200658821 is an equidigital number, since it uses as much as digits as its factorization.

18200658821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343408710.

The product of its (nonzero) digits is 61440, while the sum is 41.

The spelling of 18200658821 in words is "eighteen billion, two hundred million, six hundred fifty-eight thousand, eight hundred twenty-one".