644190658422 has 32 divisors (see below), whose sum is σ = 1304564849280. Its totient is φ = 212035586880.

The previous prime is 644190658421. The next prime is 644190658457. The reversal of 644190658422 is 224856091446.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644190658421) 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, 658722 + ... + 1312362.

It is an arithmetic number, because the mean of its divisors is an integer number (40767651540).

Almost surely, 2^644190658422 is an apocalyptic number.

644190658422 is an abundant number, since it is smaller than the sum of its proper divisors (660374190858).

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

644190658422 is a wasteful number, since it uses less digits than its factorization.

644190658422 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 655708.

The product of its (nonzero) digits is 3317760, while the sum is 51.

The spelling of 644190658422 in words is "six hundred forty-four billion, one hundred ninety million, six hundred fifty-eight thousand, four hundred twenty-two".