18135446400 has 960 divisors, whose sum is σ = 72112824960. Its totient is φ = 4478976000.

The previous prime is 18135446393. The next prime is 18135446411. The reversal of 18135446400 is 464453181.

18135446400 is a `hidden beast` number, since 1 + 8 + 1 + 3 + 5 + 4 + 4 + 640 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (960).

It is a super-2 number, since 2×18135446400² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 297302370 + ... + 297302430.

It is an arithmetic number, because the mean of its divisors is an integer number (75117526).

Almost surely, 2^18135446400 is an apocalyptic number.

18135446400 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 18135446400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36056412480).

18135446400 is an abundant number, since it is smaller than the sum of its proper divisors (53977378560).

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

18135446400 is a wasteful number, since it uses less digits than its factorization.

18135446400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165 (or 139 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

Adding to 18135446400 its reverse (464453181), we get a palindrome (18599899581).

The spelling of 18135446400 in words is "eighteen billion, one hundred thirty-five million, four hundred forty-six thousand, four hundred".