645186925369440 has 96 divisors (see below), whose sum is σ = 2258154238808160. Its totient is φ = 172049846764032.

The previous prime is 645186925369421. The next prime is 645186925369471. The reversal of 645186925369440 is 44963529681546.

It is a happy number.

645186925369440 is a `hidden beast` number, since 6 + 4 + 5 + 1 + 86 + 9 + 2 + 536 + 9 + 4 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 74674408339 + ... + 74674416978.

It is an arithmetic number, because the mean of its divisors is an integer number (23522439987585).

Almost surely, 2^{645186925369440} is an apocalyptic number.

645186925369440 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

645186925369440 is an abundant number, since it is smaller than the sum of its proper divisors (1612967313438720).

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

645186925369440 is a wasteful number, since it uses less digits than its factorization.

645186925369440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149348825341 (or 149348825327 counting only the distinct ones).

The product of its (nonzero) digits is 1343692800, while the sum is 72.

The spelling of 645186925369440 in words is "six hundred forty-five trillion, one hundred eighty-six billion, nine hundred twenty-five million, three hundred sixty-nine thousand, four hundred forty".