18199019520 has 816 divisors, whose sum is σ = 75308153760. Its totient is φ = 4152360960.

The previous prime is 18199019483. The next prime is 18199019521. The reversal of 18199019520 is 2591099181.

18199019520 is a `hidden beast` number, since 18 + 19 + 90 + 19 + 520 = 666.

It is a tau number, because it is divible by the number of its divisors (816).

It is a super-2 number, since 2×18199019520² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18199019521) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1070530552 + ... + 1070530568.

Almost surely, 2^18199019520 is an apocalyptic number.

18199019520 is a gapful number since it is divisible by the number (10) 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 18199019520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37654076880).

18199019520 is an abundant number, since it is smaller than the sum of its proper divisors (57109134240).

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

18199019520 is an equidigital number, since it uses as much as digits as its factorization.

18199019520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85 (or 38 counting only the distinct ones).

The product of its (nonzero) digits is 58320, while the sum is 45.

The spelling of 18199019520 in words is "eighteen billion, one hundred ninety-nine million, nineteen thousand, five hundred twenty".