6440478 has 16 divisors (see below), whose sum is σ = 14052096. Its totient is φ = 1951640.

The previous prime is 6440477. The next prime is 6440491. The reversal of 6440478 is 8740446.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6440471) 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, 48726 + ... + 48857.

It is an arithmetic number, because the mean of its divisors is an integer number (878256).

Almost surely, 2^6440478 is an apocalyptic number.

6440478 is an abundant number, since it is smaller than the sum of its proper divisors (7611618).

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

6440478 is a wasteful number, since it uses less digits than its factorization.

6440478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97599.

The product of its (nonzero) digits is 21504, while the sum is 33.

The square root of 6440478 is about 2537.8096855359. The cubic root of 6440478 is about 186.0541523444.

Subtracting 6440478 from its reverse (8740446), we obtain a cube (2299968 = 132³).

The spelling of 6440478 in words is "six million, four hundred forty thousand, four hundred seventy-eight".