640170518737 has 8 divisors (see below), whose sum is σ = 640725817032. Its totient is φ = 639615436800.

The previous prime is 640170518723. The next prime is 640170518759. The reversal of 640170518737 is 737815071046.

It can be written as a sum of positive squares in 4 ways, for example, as 140082524176 + 500087994561 = 374276^2 + 707169^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-640170518737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (640170513737) 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 7 ways as a sum of consecutive naturals, for example, 6173437 + ... + 6276277.

It is an arithmetic number, because the mean of its divisors is an integer number (80090727129).

Almost surely, 2^640170518737 is an apocalyptic number.

It is an amenable number.

640170518737 is a deficient number, since it is larger than the sum of its proper divisors (555298295).

640170518737 is a wasteful number, since it uses less digits than its factorization.

640170518737 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108179.

The product of its (nonzero) digits is 987840, while the sum is 49.

The spelling of 640170518737 in words is "six hundred forty billion, one hundred seventy million, five hundred eighteen thousand, seven hundred thirty-seven".