646754022720 has 504 divisors, whose sum is σ = 2428047138816. Its totient is φ = 157932343296.

The previous prime is 646754022713. The next prime is 646754022727. The reversal of 646754022720 is 27220457646.

It is a happy number.

646754022720 is a `hidden beast` number, since 6 + 4 + 67 + 540 + 2 + 27 + 20 = 666.

It is an interprime number because it is at equal distance from previous prime (646754022713) and next prime (646754022727).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646754022727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 61808209 + ... + 61818671.

Almost surely, 2^646754022720 is an apocalyptic number.

646754022720 is a gapful number since it is divisible by the number (60) 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 646754022720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1214023569408).

646754022720 is an abundant number, since it is smaller than the sum of its proper divisors (1781293116096).

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

646754022720 is a wasteful number, since it uses less digits than its factorization.

646754022720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10639 (or 10613 counting only the distinct ones).

The product of its (nonzero) digits is 1128960, while the sum is 45.

The spelling of 646754022720 in words is "six hundred forty-six billion, seven hundred fifty-four million, twenty-two thousand, seven hundred twenty".