1666742400 has 384 divisors, whose sum is σ = 6192460800. Its totient is φ = 437760000.

The previous prime is 1666742359. The next prime is 1666742417. The reversal of 1666742400 is 42476661.

It is a tau number, because it is divible by the number of its divisors (384).

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 47 ways as a sum of consecutive naturals, for example, 8726305 + ... + 8726495.

It is an arithmetic number, because the mean of its divisors is an integer number (16126200).

Almost surely, 2^1666742400 is an apocalyptic number.

1666742400 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 1666742400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3096230400).

1666742400 is an abundant number, since it is smaller than the sum of its proper divisors (4525718400).

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

1666742400 is a wasteful number, since it uses less digits than its factorization.

1666742400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 325 (or 302 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 36.

The square root of 1666742400 is about 40825.7565759656. The cubic root of 1666742400 is about 1185.6490595838.

The spelling of 1666742400 in words is "one billion, six hundred sixty-six million, seven hundred forty-two thousand, four hundred".