660187620 has 72 divisors (see below), whose sum is σ = 2008142136. Its totient is φ = 175560192.

The previous prime is 660187609. The next prime is 660187637. The reversal of 660187620 is 26781066.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 79281216 + 580906404 = 8904^2 + 24102^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

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, 62224 + ... + 72056.

It is an arithmetic number, because the mean of its divisors is an integer number (27890863).

Almost surely, 2^660187620 is an apocalyptic number.

660187620 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 660187620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1004071068).

660187620 is an abundant number, since it is smaller than the sum of its proper divisors (1347954516).

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

660187620 is a wasteful number, since it uses less digits than its factorization.

660187620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10221 (or 10216 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 660187620 is about 25694.1164471558. The cubic root of 660187620 is about 870.7412628152.

The spelling of 660187620 in words is "six hundred sixty million, one hundred eighty-seven thousand, six hundred twenty".