644434270158 has 32 divisors (see below), whose sum is σ = 1473027462144. Its totient is φ = 184119721632.

The previous prime is 644434270157. The next prime is 644434270201. The reversal of 644434270158 is 851072434446.

644434270158 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644434270157) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1894516 + ... + 2208632.

It is an arithmetic number, because the mean of its divisors is an integer number (46032108192).

Almost surely, 2^644434270158 is an apocalyptic number.

644434270158 is an abundant number, since it is smaller than the sum of its proper divisors (828593191986).

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

644434270158 is a wasteful number, since it uses less digits than its factorization.

644434270158 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 362976.

The product of its (nonzero) digits is 2580480, while the sum is 48.

The spelling of 644434270158 in words is "six hundred forty-four billion, four hundred thirty-four million, two hundred seventy thousand, one hundred fifty-eight".