646202456640 has 896 divisors, whose sum is σ = 2507065344000. Its totient is φ = 155733000192.

The previous prime is 646202456629. The next prime is 646202456651. The reversal of 646202456640 is 46654202646.

646202456640 is a `hidden beast` number, since 6 + 4 + 6 + 20 + 24 + 566 + 40 = 666.

It is an interprime number because it is at equal distance from previous prime (646202456629) and next prime (646202456651).

It is a super-2 number, since 2×646202456640² (a number of 24 digits) contains 22 as substring.

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

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 127 ways as a sum of consecutive naturals, for example, 1269552706 + ... + 1269553214.

It is an arithmetic number, because the mean of its divisors is an integer number (2798064000).

Almost surely, 2^646202456640 is an apocalyptic number.

646202456640 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 646202456640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1253532672000).

646202456640 is an abundant number, since it is smaller than the sum of its proper divisors (1860862887360).

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

646202456640 is a wasteful number, since it uses less digits than its factorization.

646202456640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 764 (or 748 counting only the distinct ones).

The product of its (nonzero) digits is 1658880, while the sum is 45.

The spelling of 646202456640 in words is "six hundred forty-six billion, two hundred two million, four hundred fifty-six thousand, six hundred forty".