660726740 has 12 divisors (see below), whose sum is σ = 1387526196. Its totient is φ = 264290688.

The previous prime is 660726719. The next prime is 660726757. The reversal of 660726740 is 47627066.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 433139344 + 227587396 = 20812^2 + 15086^2 .

It is a junction number, because it is equal to n+sod(n) for n = 660726694 and 660726703.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16518149 + ... + 16518188.

It is an arithmetic number, because the mean of its divisors is an integer number (115627183).

Almost surely, 2^660726740 is an apocalyptic number.

It is an amenable number.

660726740 is an abundant number, since it is smaller than the sum of its proper divisors (726799456).

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

660726740 is a wasteful number, since it uses less digits than its factorization.

660726740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33036346 (or 33036344 counting only the distinct ones).

The product of its (nonzero) digits is 84672, while the sum is 38.

The square root of 660726740 is about 25704.6054239313. The cubic root of 660726740 is about 870.9782188415.

The spelling of 660726740 in words is "six hundred sixty million, seven hundred twenty-six thousand, seven hundred forty".