667651664550 has 96 divisors (see below), whose sum is σ = 1784533595040. Its totient is φ = 164216908800.

The previous prime is 667651664503. The next prime is 667651664557. The reversal of 667651664550 is 55466156766.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667651664557) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2380740 + ... + 2646360.

It is an arithmetic number, because the mean of its divisors is an integer number (18588891615).

Almost surely, 2^667651664550 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 667651664550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (892266797520).

667651664550 is an abundant number, since it is smaller than the sum of its proper divisors (1116881930490).

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

667651664550 is a wasteful number, since it uses less digits than its factorization.

667651664550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266938 (or 266933 counting only the distinct ones).

The product of its (nonzero) digits is 27216000, while the sum is 57.

The spelling of 667651664550 in words is "six hundred sixty-seven billion, six hundred fifty-one million, six hundred sixty-four thousand, five hundred fifty".