6440264 has 8 divisors (see below), whose sum is σ = 12075510. Its totient is φ = 3220128.

The previous prime is 6440249. The next prime is 6440303. The reversal of 6440264 is 4620446.

It can be written as a sum of positive squares in only one way, i.e., 5522500 + 917764 = 2350^2 + 958^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 402509 + ... + 402524.

Almost surely, 2^6440264 is an apocalyptic number.

It is an amenable number.

6440264 is a deficient number, since it is larger than the sum of its proper divisors (5635246).

6440264 is a wasteful number, since it uses less digits than its factorization.

6440264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 805039 (or 805035 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 26.

The square root of 6440264 is about 2537.7675228437. The cubic root of 6440264 is about 186.0520916262.

The spelling of 6440264 in words is "six million, four hundred forty thousand, two hundred sixty-four".