640231177 has 2 divisors, whose sum is σ = 640231178. Its totient is φ = 640231176.

The previous prime is 640231159. The next prime is 640231213. The reversal of 640231177 is 771132046.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 616230976 + 24000201 = 24824^2 + 4899^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-640231177 is a prime.

It is equal to p_33311956 and since 640231177 and 33311956 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (640231117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320115588 + 320115589.

It is an arithmetic number, because the mean of its divisors is an integer number (320115589).

Almost surely, 2^640231177 is an apocalyptic number.

It is an amenable number.

640231177 is a deficient number, since it is larger than the sum of its proper divisors (1).

640231177 is an equidigital number, since it uses as much as digits as its factorization.

640231177 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7056, while the sum is 31.

The square root of 640231177 is about 25302.7899054630. The cubic root of 640231177 is about 861.8776251361.

The spelling of 640231177 in words is "six hundred forty million, two hundred thirty-one thousand, one hundred seventy-seven".