644970719232 has 1920 divisors, whose sum is σ = 2557229875200. Its totient is φ = 157659955200.

The previous prime is 644970719203. The next prime is 644970719243. The reversal of 644970719232 is 232917079446.

644970719232 is a `hidden beast` number, since 6 + 449 + 7 + 0 + 7 + 192 + 3 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 15730993132 + ... + 15730993172.

It is an arithmetic number, because the mean of its divisors is an integer number (1331890560).

Almost surely, 2^644970719232 is an apocalyptic number.

644970719232 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 644970719232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1278614937600).

644970719232 is an abundant number, since it is smaller than the sum of its proper divisors (1912259155968).

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

644970719232 is a wasteful number, since it uses less digits than its factorization.

644970719232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155 (or 126 counting only the distinct ones).

The product of its (nonzero) digits is 4572288, while the sum is 54.

The spelling of 644970719232 in words is "six hundred forty-four billion, nine hundred seventy million, seven hundred nineteen thousand, two hundred thirty-two".