640131227 has 8 divisors (see below), whose sum is σ = 647512656. Its totient is φ = 632765952.

The previous prime is 640131203. The next prime is 640131229. The reversal of 640131227 is 722131046.

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

It is a cyclic number.

It is not a de Polignac number, because 640131227 - 2²² = 635936923 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 640131196 and 640131205.

It is not an unprimeable number, because it can be changed into a prime (640131229) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 87368 + ... + 94410.

It is an arithmetic number, because the mean of its divisors is an integer number (80939082).

Almost surely, 2^640131227 is an apocalyptic number.

640131227 is a deficient number, since it is larger than the sum of its proper divisors (7381429).

640131227 is an equidigital number, since it uses as much as digits as its factorization.

640131227 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8077.

The product of its (nonzero) digits is 2016, while the sum is 26.

The square root of 640131227 is about 25300.8147497269. The cubic root of 640131227 is about 861.8327719878.

The spelling of 640131227 in words is "six hundred forty million, one hundred thirty-one thousand, two hundred twenty-seven".