6445887 has 8 divisors (see below), whose sum is σ = 9822336. Its totient is φ = 3683352.

The previous prime is 6445871. The next prime is 6445919. The reversal of 6445887 is 7885446.

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

It is not a de Polignac number, because 6445887 - 2⁴ = 6445871 is a prime.

6445887 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6441887) 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, 153453 + ... + 153494.

It is an arithmetic number, because the mean of its divisors is an integer number (1227792).

Almost surely, 2^6445887 is an apocalyptic number.

6445887 is a deficient number, since it is larger than the sum of its proper divisors (3376449).

6445887 is a wasteful number, since it uses less digits than its factorization.

6445887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 306957.

The product of its digits is 215040, while the sum is 42.

The square root of 6445887 is about 2538.8751446261. The cubic root of 6445887 is about 186.1062232885.

Subtracting from 6445887 its sum of digits (42), we obtain a triangular number (6445845 = T₃₅₉₀).

The spelling of 6445887 in words is "six million, four hundred forty-five thousand, eight hundred eighty-seven".