645863661300000 has 1152 divisors, whose sum is σ = 2496688489209600. Its totient is φ = 144116121600000.

The previous prime is 645863661299981. The next prime is 645863661300019. The reversal of 645863661300000 is 3166368546.

It is an interprime number because it is at equal distance from previous prime (645863661299981) and next prime (645863661300019).

It is a super-2 number, since 2×645863661300000² (a number of 30 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 15143678676 + ... + 15143721324.

It is an arithmetic number, because the mean of its divisors is an integer number (2167264313550).

Almost surely, 2^{645863661300000} is an apocalyptic number.

645863661300000 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 645863661300000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1248344244604800).

645863661300000 is an abundant number, since it is smaller than the sum of its proper divisors (1850824827909600).

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

645863661300000 is a wasteful number, since it uses less digits than its factorization.

645863661300000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43064 (or 43036 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 48.

The spelling of 645863661300000 in words is "six hundred forty-five trillion, eight hundred sixty-three billion, six hundred sixty-one million, three hundred thousand".