18219639811 has 8 divisors (see below), whose sum is σ = 18539468640. Its totient is φ = 17901709632.

The previous prime is 18219639793. The next prime is 18219639829. The reversal of 18219639811 is 11893691281.

It is an interprime number because it is at equal distance from previous prime (18219639793) and next prime (18219639829).

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

It is a cyclic number.

It is not a de Polignac number, because 18219639811 - 2⁹ = 18219639299 is a prime.

It is a super-2 number, since 2×18219639811² (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 (18219639311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 455296 + ... + 493693.

It is an arithmetic number, because the mean of its divisors is an integer number (2317433580).

Almost surely, 2^18219639811 is an apocalyptic number.

18219639811 is a deficient number, since it is larger than the sum of its proper divisors (319828829).

18219639811 is an equidigital number, since it uses as much as digits as its factorization.

18219639811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 949325.

The product of its digits is 186624, while the sum is 49.

The spelling of 18219639811 in words is "eighteen billion, two hundred nineteen million, six hundred thirty-nine thousand, eight hundred eleven".