666097740 has 432 divisors, whose sum is σ = 2697903936. Its totient is φ = 129761280.

The previous prime is 666097711. The next prime is 666097741. The reversal of 666097740 is 47790666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (666097741) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 2591692 + ... + 2591948.

It is an arithmetic number, because the mean of its divisors is an integer number (6245148).

Almost surely, 2^666097740 is an apocalyptic number.

666097740 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 666097740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1348951968).

666097740 is an abundant number, since it is smaller than the sum of its proper divisors (2031806196).

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

666097740 is a wasteful number, since it uses less digits than its factorization.

666097740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 318 (or 302 counting only the distinct ones).

The product of its (nonzero) digits is 381024, while the sum is 45.

The square root of 666097740 is about 25808.8694056907. The cubic root of 666097740 is about 873.3318924022.

The spelling of 666097740 in words is "six hundred sixty-six million, ninety-seven thousand, seven hundred forty".