1668737280 has 144 divisors (see below), whose sum is σ = 6090989184. Its totient is φ = 381419520.

The previous prime is 1668737267. The next prime is 1668737293. The reversal of 1668737280 is 827378661.

It is an interprime number because it is at equal distance from previous prime (1668737267) and next prime (1668737293).

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4161 + ... + 57920.

It is an arithmetic number, because the mean of its divisors is an integer number (42298536).

Almost surely, 2^1668737280 is an apocalyptic number.

1668737280 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 1668737280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3045494592).

1668737280 is an abundant number, since it is smaller than the sum of its proper divisors (4422251904).

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

1668737280 is an equidigital number, since it uses as much as digits as its factorization.

1668737280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62112 (or 62098 counting only the distinct ones).

The product of its (nonzero) digits is 677376, while the sum is 48.

The square root of 1668737280 is about 40850.1809053522. The cubic root of 1668737280 is about 1186.1218950175.

The spelling of 1668737280 in words is "one billion, six hundred sixty-eight million, seven hundred thirty-seven thousand, two hundred eighty".