18381818201 has 4 divisors (see below), whose sum is σ = 19181027712. Its totient is φ = 17582608692.

The previous prime is 18381818167. The next prime is 18381818209. The reversal of 18381818201 is 10281818381.

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 18381818201 - 2³⁴ = 1201949017 is a prime.

It is a super-2 number, since 2×18381818201² (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 (18381818209) 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, 399604721 + ... + 399604766.

It is an arithmetic number, because the mean of its divisors is an integer number (4795256928).

Almost surely, 2^18381818201 is an apocalyptic number.

It is an amenable number.

18381818201 is a deficient number, since it is larger than the sum of its proper divisors (799209511).

18381818201 is an equidigital number, since it uses as much as digits as its factorization.

18381818201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 799209510.

The product of its (nonzero) digits is 24576, while the sum is 41.

The spelling of 18381818201 in words is "eighteen billion, three hundred eighty-one million, eight hundred eighteen thousand, two hundred one".