1816622121600 has 3456 divisors, whose sum is σ = 8640408853440. Its totient is φ = 370262016000.

The previous prime is 1816622121563. The next prime is 1816622121679. The reversal of 1816622121600 is 61212266181.

It is a happy number.

1816622121600 is a `hidden beast` number, since 1 + 8 + 1 + 6 + 6 + 2 + 21 + 21 + 600 = 666.

It is a tau number, because it is divible by the number of its divisors (3456).

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

It is an unprimeable number.

It is a polite number, since it can be written in 431 ways as a sum of consecutive naturals, for example, 58600713585 + ... + 58600713615.

Almost surely, 2^{1816622121600} is an apocalyptic number.

1816622121600 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 1816622121600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4320204426720).

1816622121600 is an abundant number, since it is smaller than the sum of its proper divisors (6823786731840).

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

1816622121600 is a wasteful number, since it uses less digits than its factorization.

1816622121600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142 (or 82 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

Adding to 1816622121600 its reverse (61212266181), we get a palindrome (1877834387781).

The spelling of 1816622121600 in words is "one trillion, eight hundred sixteen billion, six hundred twenty-two million, one hundred twenty-one thousand, six hundred".