6441857987 has 4 divisors (see below), whose sum is σ = 6443224920. Its totient is φ = 6440491056.

The previous prime is 6441857971. The next prime is 6441857999. The reversal of 6441857987 is 7897581446.

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 6441857987 - 2⁴ = 6441857971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6441853987) 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, 676373 + ... + 685830.

It is an arithmetic number, because the mean of its divisors is an integer number (1610806230).

Almost surely, 2^6441857987 is an apocalyptic number.

6441857987 is a deficient number, since it is larger than the sum of its proper divisors (1366933).

6441857987 is a wasteful number, since it uses less digits than its factorization.

6441857987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1366932.

The product of its digits is 13547520, while the sum is 59.

The square root of 6441857987 is about 80261.1860552783. The cubic root of 6441857987 is about 1860.6743986620.

The spelling of 6441857987 in words is "six billion, four hundred forty-one million, eight hundred fifty-seven thousand, nine hundred eighty-seven".