551531520666 has 128 divisors (see below), whose sum is σ = 1420392038400. Its totient is φ = 155372256000.

The previous prime is 551531520629. The next prime is 551531520667. The reversal of 551531520666 is 666025135155.

It is not an unprimeable number, because it can be changed into a prime (551531520667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 22414066 + ... + 22438658.

It is an arithmetic number, because the mean of its divisors is an integer number (11096812800).

Almost surely, 2^551531520666 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 551531520666, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (710196019200).

551531520666 is an abundant number, since it is smaller than the sum of its proper divisors (868860517734).

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

551531520666 is a wasteful number, since it uses less digits than its factorization.

551531520666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25441 (or 25435 counting only the distinct ones).

The product of its (nonzero) digits is 810000, while the sum is 45.

The spelling of 551531520666 in words is "five hundred fifty-one billion, five hundred thirty-one million, five hundred twenty thousand, six hundred sixty-six".