1666022774400 has 672 divisors, whose sum is σ = 6439065685920. Its totient is φ = 424942848000.

The previous prime is 1666022774393. The next prime is 1666022774411. The reversal of 1666022774400 is 44772206661.

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

It is an unprimeable number.

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 83 ways as a sum of consecutive naturals, for example, 53638875 + ... + 53669925.

It is an arithmetic number, because the mean of its divisors is an integer number (9581942985).

Almost surely, 2^{1666022774400} is an apocalyptic number.

1666022774400 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 1666022774400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3219532842960).

1666022774400 is an abundant number, since it is smaller than the sum of its proper divisors (4773042911520).

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

1666022774400 is an equidigital number, since it uses as much as digits as its factorization.

1666022774400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31116 (or 31084 counting only the distinct ones).

The product of its (nonzero) digits is 677376, while the sum is 45.

The spelling of 1666022774400 in words is "one trillion, six hundred sixty-six billion, twenty-two million, seven hundred seventy-four thousand, four hundred".