640095277 has 8 divisors (see below), whose sum is σ = 649139832. Its totient is φ = 631104000.

The previous prime is 640095259. The next prime is 640095289. The reversal of 640095277 is 772590046.

It can be written as a sum of positive squares in 4 ways, for example, as 332478756 + 307616521 = 18234^2 + 17539^2 .

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-640095277 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640099277) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11193 + ... + 37489.

It is an arithmetic number, because the mean of its divisors is an integer number (81142479).

Almost surely, 2^640095277 is an apocalyptic number.

It is an amenable number.

640095277 is a deficient number, since it is larger than the sum of its proper divisors (9044555).

640095277 is a wasteful number, since it uses less digits than its factorization.

640095277 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26639.

The product of its (nonzero) digits is 105840, while the sum is 40.

The square root of 640095277 is about 25300.1042883226. The cubic root of 640095277 is about 861.8166380729.

The spelling of 640095277 in words is "six hundred forty million, ninety-five thousand, two hundred seventy-seven".