6444990 has 48 divisors (see below), whose sum is σ = 17643600. Its totient is φ = 1627776.

The previous prime is 6444979. The next prime is 6445003. The reversal of 6444990 is 994446.

6444990 is a `hidden beast` number, since 644 + 4 + 9 + 9 + 0 = 666.

It is a super-2 number, since 2×6444990² = 83075792200200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 175 + ... + 3594.

It is an arithmetic number, because the mean of its divisors is an integer number (367575).

Almost surely, 2^6444990 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6444990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8821800).

6444990 is an abundant number, since it is smaller than the sum of its proper divisors (11198610).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6444990 is a wasteful number, since it uses less digits than its factorization.

6444990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3801 (or 3798 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 6444990 is about 2538.6984854449. The cubic root of 6444990 is about 186.0975901335.

It can be divided in two parts, 64 and 44990, that added together give a palindrome (45054).

The spelling of 6444990 in words is "six million, four hundred forty-four thousand, nine hundred ninety".