18191564952 has 256 divisors, whose sum is σ = 53568345600. Its totient is φ = 5129625600.

The previous prime is 18191564939. The next prime is 18191564977. The reversal of 18191564952 is 25946519181.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a junction number, because it is equal to n+sod(n) for n = 18191564895 and 18191564904.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 75483552 + ... + 75483792.

It is an arithmetic number, because the mean of its divisors is an integer number (209251350).

Almost surely, 2^18191564952 is an apocalyptic number.

18191564952 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18191564952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26784172800).

18191564952 is an abundant number, since it is smaller than the sum of its proper divisors (35376780648).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18191564952 is a wasteful number, since it uses less digits than its factorization.

18191564952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 439 (or 413 counting only the distinct ones).

The product of its digits is 777600, while the sum is 51.

The spelling of 18191564952 in words is "eighteen billion, one hundred ninety-one million, five hundred sixty-four thousand, nine hundred fifty-two".