6440263 has 8 divisors (see below), whose sum is σ = 6935760. Its totient is φ = 5957760.

The previous prime is 6440249. The next prime is 6440303. The reversal of 6440263 is 3620446.

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

It is a cyclic number.

It is not a de Polignac number, because 6440263 - 2⁹ = 6439751 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6470263) 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, 2208 + ... + 4213.

It is an arithmetic number, because the mean of its divisors is an integer number (866970).

Almost surely, 2^6440263 is an apocalyptic number.

6440263 is a deficient number, since it is larger than the sum of its proper divisors (495497).

6440263 is a wasteful number, since it uses less digits than its factorization.

6440263 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6497.

The product of its (nonzero) digits is 3456, while the sum is 25.

The square root of 6440263 is about 2537.7673258201. The cubic root of 6440263 is about 186.0520819966.

It can be divided in two parts, 6440 and 263, that multiplied together give a triangular number (1693720 = T₁₈₄₀).

The spelling of 6440263 in words is "six million, four hundred forty thousand, two hundred sixty-three".