660805740 has 144 divisors (see below), whose sum is σ = 2297568000. Its totient is φ = 150595200.

The previous prime is 660805729. The next prime is 660805751. The reversal of 660805740 is 47508066.

It is a happy number.

660805740 is a `hidden beast` number, since 6 + 6 + 0 + 80 + 574 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (660805729) and next prime (660805751).

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

It is a junction number, because it is equal to n+sod(n) for n = 660805695 and 660805704.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 628215 + ... + 629265.

Almost surely, 2^660805740 is an apocalyptic number.

660805740 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 660805740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1148784000).

660805740 is an abundant number, since it is smaller than the sum of its proper divisors (1636762260).

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

660805740 is a wasteful number, since it uses less digits than its factorization.

660805740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1572 (or 1567 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The square root of 660805740 is about 25706.1420676071. The cubic root of 660805740 is about 871.0129303861.

The spelling of 660805740 in words is "six hundred sixty million, eight hundred five thousand, seven hundred forty".