6665589840 has 480 divisors, whose sum is σ = 27095337216. Its totient is φ = 1322680320.

The previous prime is 6665589817. The next prime is 6665589877. The reversal of 6665589840 is 489855666.

It is a happy number.

It is a super-2 number, since 2×6665589840² = 88860175830222451200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 4825950 + ... + 4827330.

Almost surely, 2^6665589840 is an apocalyptic number.

6665589840 is a gapful number since it is divisible by the number (60) 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 6665589840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13547668608).

6665589840 is an abundant number, since it is smaller than the sum of its proper divisors (20429747376).

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

6665589840 is a wasteful number, since it uses less digits than its factorization.

6665589840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1447 (or 1428 counting only the distinct ones).

The product of its (nonzero) digits is 12441600, while the sum is 57.

The square root of 6665589840 is about 81643.0636367842. The cubic root of 6665589840 is about 1881.9707190366.

The spelling of 6665589840 in words is "six billion, six hundred sixty-five million, five hundred eighty-nine thousand, eight hundred forty".