641087999 has 4 divisors (see below), whose sum is σ = 646136064. Its totient is φ = 636039936.

The previous prime is 641087981. The next prime is 641088023. The reversal of 641087999 is 999780146.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 641087999 - 2⁸ = 641087743 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 641087999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641087939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2523842 + ... + 2524095.

It is an arithmetic number, because the mean of its divisors is an integer number (161534016).

Almost surely, 2^641087999 is an apocalyptic number.

641087999 is a deficient number, since it is larger than the sum of its proper divisors (5048065).

641087999 is a wasteful number, since it uses less digits than its factorization.

641087999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5048064.

The product of its (nonzero) digits is 979776, while the sum is 53.

The square root of 641087999 is about 25319.7156184662. The cubic root of 641087999 is about 862.2619376301.

The spelling of 641087999 in words is "six hundred forty-one million, eighty-seven thousand, nine hundred ninety-nine".