640172037737 has 16 divisors (see below), whose sum is σ = 671566721040. Its totient is φ = 609404931072.

The previous prime is 640172037727. The next prime is 640172037751. The reversal of 640172037737 is 737730271046.

It can be written as a sum of positive squares in 8 ways, for example, as 17491649536 + 622680388201 = 132256^2 + 789101^2 .

It is a cyclic number.

It is not a de Polignac number, because 640172037737 - 2³² = 635877070441 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 640172037691 and 640172037700.

It is not an unprimeable number, because it can be changed into a prime (640172037727) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5824463 + ... + 5933355.

It is an arithmetic number, because the mean of its divisors is an integer number (41972920065).

Almost surely, 2^640172037737 is an apocalyptic number.

It is an amenable number.

640172037737 is a deficient number, since it is larger than the sum of its proper divisors (31394683303).

640172037737 is a wasteful number, since it uses less digits than its factorization.

640172037737 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111772.

The product of its (nonzero) digits is 1037232, while the sum is 47.

The spelling of 640172037737 in words is "six hundred forty billion, one hundred seventy-two million, thirty-seven thousand, seven hundred thirty-seven".