6640434 has 16 divisors (see below), whose sum is σ = 14756640. Its totient is φ = 2213460.

The previous prime is 6640429. The next prime is 6640441. The reversal of 6640434 is 4340466.

It is a happy number.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an Ulam number.

It is a nialpdrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 6640398 and 6640407.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 61432 + ... + 61539.

It is an arithmetic number, because the mean of its divisors is an integer number (922290).

Almost surely, 2^6640434 is an apocalyptic number.

6640434 is an abundant number, since it is smaller than the sum of its proper divisors (8116206).

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

6640434 is a wasteful number, since it uses less digits than its factorization.

6640434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122982 (or 122976 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 27.

The square root of 6640434 is about 2576.9039563010. The cubic root of 6640434 is about 187.9600224336.

Subtracting from 6640434 its reverse (4340466), we obtain a cube (2299968 = 132³).

The spelling of 6640434 in words is "six million, six hundred forty thousand, four hundred thirty-four".