667515620 has 72 divisors (see below), whose sum is σ = 1484474040. Its totient is φ = 251829760.

The previous prime is 667515613. The next prime is 667515623. The reversal of 667515620 is 26515766.

It can be written as a sum of positive squares in 4 ways, for example, as 32878756 + 634636864 = 5734^2 + 25192^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667515623) 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 23 ways as a sum of consecutive naturals, for example, 1280960 + ... + 1281480.

It is an arithmetic number, because the mean of its divisors is an integer number (20617695).

Almost surely, 2^667515620 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 667515620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (742237020).

667515620 is an abundant number, since it is smaller than the sum of its proper divisors (816958420).

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

667515620 is a wasteful number, since it uses less digits than its factorization.

667515620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 653 (or 604 counting only the distinct ones).

The product of its (nonzero) digits is 75600, while the sum is 38.

The square root of 667515620 is about 25836.3236548856. The cubic root of 667515620 is about 873.9511219692.

The spelling of 667515620 in words is "six hundred sixty-seven million, five hundred fifteen thousand, six hundred twenty".