644710122 has 48 divisors (see below), whose sum is σ = 1597931712. Its totient is φ = 184029120.

The previous prime is 644710103. The next prime is 644710189. The reversal of 644710122 is 221017446.

644710122 is a `hidden beast` number, since 644 + 7 + 1 + 0 + 12 + 2 = 666.

It is a super-2 number, since 2×644710122² = 831302282818509768, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 196318 + ... + 199574.

It is an arithmetic number, because the mean of its divisors is an integer number (33290244).

Almost surely, 2^644710122 is an apocalyptic number.

644710122 is an abundant number, since it is smaller than the sum of its proper divisors (953221590).

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

644710122 is a wasteful number, since it uses less digits than its factorization.

644710122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4843 (or 4840 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 644710122 is about 25391.1425894937. The cubic root of 644710122 is about 863.8828046416.

Adding to 644710122 its reverse (221017446), we get a palindrome (865727568).

The spelling of 644710122 in words is "six hundred forty-four million, seven hundred ten thousand, one hundred twenty-two".