1667738680 has 64 divisors (see below), whose sum is σ = 3978576000. Its totient is φ = 627398784.

The previous prime is 1667738659. The next prime is 1667738687. The reversal of 1667738680 is 868377661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1667738687) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 97747 + ... + 113533.

It is an arithmetic number, because the mean of its divisors is an integer number (62165250).

Almost surely, 2^1667738680 is an apocalyptic number.

1667738680 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 1667738680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1989288000).

1667738680 is an abundant number, since it is smaller than the sum of its proper divisors (2310837320).

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

1667738680 is a wasteful number, since it uses less digits than its factorization.

1667738680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15956 (or 15952 counting only the distinct ones).

The product of its (nonzero) digits is 2032128, while the sum is 52.

The square root of 1667738680 is about 40837.9563641473. The cubic root of 1667738680 is about 1185.8852494843.

The spelling of 1667738680 in words is "one billion, six hundred sixty-seven million, seven hundred thirty-eight thousand, six hundred eighty".