644550123022 has 8 divisors (see below), whose sum is σ = 1041196352616. Its totient is φ = 297484672152.

The previous prime is 644550123001. The next prime is 644550123031. The reversal of 644550123022 is 220321055446.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×644550123022² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12395194648 + ... + 12395194699.

It is an arithmetic number, because the mean of its divisors is an integer number (130149544077).

Almost surely, 2^644550123022 is an apocalyptic number.

644550123022 is a deficient number, since it is larger than the sum of its proper divisors (396646229594).

644550123022 is a wasteful number, since it uses less digits than its factorization.

644550123022 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24790389362.

The product of its (nonzero) digits is 57600, while the sum is 34.

Adding to 644550123022 its reverse (220321055446), we get a palindrome (864871178468).

The spelling of 644550123022 in words is "six hundred forty-four billion, five hundred fifty million, one hundred twenty-three thousand, twenty-two".