640182671 has 4 divisors (see below), whose sum is σ = 640794000. Its totient is φ = 639571344.

The previous prime is 640182659. The next prime is 640182677. The reversal of 640182671 is 176281046.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 176281046 = 2 ⋅88140523.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-640182671 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 (640182677) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 304091 + ... + 306188.

It is an arithmetic number, because the mean of its divisors is an integer number (160198500).

Almost surely, 2^640182671 is an apocalyptic number.

640182671 is a deficient number, since it is larger than the sum of its proper divisors (611329).

640182671 is a wasteful number, since it uses less digits than its factorization.

640182671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 611328.

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 640182671 is about 25301.8313764044. The cubic root of 640182671 is about 861.8558583674.

The spelling of 640182671 in words is "six hundred forty million, one hundred eighty-two thousand, six hundred seventy-one".