666155555560 has 64 divisors (see below), whose sum is σ = 1651298400000. Its totient is φ = 239839968000.

The previous prime is 666155555543. The next prime is 666155555599. The reversal of 666155555560 is 65555551666.

It is a Harshad number since it is a multiple of its sum of digits (55).

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, 7450560 + ... + 7539439.

It is an arithmetic number, because the mean of its divisors is an integer number (25801537500).

Almost surely, 2^666155555560 is an apocalyptic number.

It is an amenable number.

666155555560 is an abundant number, since it is smaller than the sum of its proper divisors (985142844440).

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

666155555560 is a wasteful number, since it uses less digits than its factorization.

666155555560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14990122 (or 14990118 counting only the distinct ones).

The product of its (nonzero) digits is 20250000, while the sum is 55.

The spelling of 666155555560 in words is "six hundred sixty-six billion, one hundred fifty-five million, five hundred fifty-five thousand, five hundred sixty".