1666217448 has 192 divisors, whose sum is σ = 5335200000. Its totient is φ = 459841536.

The previous prime is 1666217429. The next prime is 1666217467. The reversal of 1666217448 is 8447126661.

It is an interprime number because it is at equal distance from previous prime (1666217429) and next prime (1666217467).

It is a nude number because it is divisible by every one of its digits.

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, 3710728 + ... + 3711176.

It is an arithmetic number, because the mean of its divisors is an integer number (27787500).

Almost surely, 2^1666217448 is an apocalyptic number.

1666217448 is a gapful number since it is divisible by the number (18) 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 1666217448, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2667600000).

1666217448 is an abundant number, since it is smaller than the sum of its proper divisors (3668982552).

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

1666217448 is a wasteful number, since it uses less digits than its factorization.

1666217448 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 704 (or 697 counting only the distinct ones).

The product of its digits is 387072, while the sum is 45.

The square root of 1666217448 is about 40819.3268930295. The cubic root of 1666217448 is about 1185.5245704004.

The spelling of 1666217448 in words is "one billion, six hundred sixty-six million, two hundred seventeen thousand, four hundred forty-eight".