6665221550 has 48 divisors (see below), whose sum is σ = 13383362160. Its totient is φ = 2455031040.

The previous prime is 6665221517. The next prime is 6665221571. The reversal of 6665221550 is 551225666.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 260114 + ... + 284586.

It is an arithmetic number, because the mean of its divisors is an integer number (278820045).

Almost surely, 2^6665221550 is an apocalyptic number.

6665221550 is an abundant number, since it is smaller than the sum of its proper divisors (6718140610).

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

6665221550 is a wasteful number, since it uses less digits than its factorization.

6665221550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24917 (or 24912 counting only the distinct ones).

The product of its (nonzero) digits is 108000, while the sum is 38.

The square root of 6665221550 is about 81640.8081170195. The cubic root of 6665221550 is about 1881.9360572498.

The spelling of 6665221550 in words is "six billion, six hundred sixty-five million, two hundred twenty-one thousand, five hundred fifty".