644462142 has 16 divisors (see below), whose sum is σ = 1301439360. Its totient is φ = 212734872.

The previous prime is 644462089. The next prime is 644462207. The reversal of 644462142 is 241264446.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 520792 + ... + 522027.

It is an arithmetic number, because the mean of its divisors is an integer number (81339960).

Almost surely, 2^644462142 is an apocalyptic number.

644462142 is an abundant number, since it is smaller than the sum of its proper divisors (656977218).

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

644462142 is a wasteful number, since it uses less digits than its factorization.

644462142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1042927.

The product of its digits is 36864, while the sum is 33.

The square root of 644462142 is about 25386.2589209202. The cubic root of 644462142 is about 863.7720297249.

It can be divided in two parts, 6444 and 62142, that added together give a palindrome (68586).

The spelling of 644462142 in words is "six hundred forty-four million, four hundred sixty-two thousand, one hundred forty-two".