1668241440 has 192 divisors, whose sum is σ = 6027678720. Its totient is φ = 430479360.

The previous prime is 1668241423. The next prime is 1668241517. The reversal of 1668241440 is 441428661.

It is a happy number.

1668241440 is a `hidden beast` number, since 166 + 82 + 414 + 4 + 0 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 1668241395 and 1668241404.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 127692 + ... + 140148.

It is an arithmetic number, because the mean of its divisors is an integer number (31394160).

Almost surely, 2^1668241440 is an apocalyptic number.

1668241440 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 1668241440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3013839360).

1668241440 is an abundant number, since it is smaller than the sum of its proper divisors (4359437280).

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

1668241440 is a wasteful number, since it uses less digits than its factorization.

1668241440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12512 (or 12498 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The square root of 1668241440 is about 40844.1114482859. Note that the first 3 decimals coincide. The cubic root of 1668241440 is about 1186.0044039964.

The spelling of 1668241440 in words is "one billion, six hundred sixty-eight million, two hundred forty-one thousand, four hundred forty".