644375134 has 16 divisors (see below), whose sum is σ = 1046152800. Its totient is φ = 295907040.

The previous prime is 644375131. The next prime is 644375201. The reversal of 644375134 is 431573446.

It is a junction number, because it is equal to n+sod(n) for n = 644375093 and 644375102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644375131) 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, 57097 + ... + 67444.

It is an arithmetic number, because the mean of its divisors is an integer number (65384550).

Almost surely, 2^644375134 is an apocalyptic number.

644375134 is a deficient number, since it is larger than the sum of its proper divisors (401777666).

644375134 is a wasteful number, since it uses less digits than its factorization.

644375134 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124755.

The product of its digits is 120960, while the sum is 37.

The square root of 644375134 is about 25384.5451800894. The cubic root of 644375134 is about 863.7331557273.

The spelling of 644375134 in words is "six hundred forty-four million, three hundred seventy-five thousand, one hundred thirty-four".