1945638864 has 180 divisors, whose sum is σ = 6088717440. Its totient is φ = 579121920.

The previous prime is 1945638841. The next prime is 1945638883. The reversal of 1945638864 is 4688365491.

1945638864 is a `hidden beast` number, since 19 + 4 + 563 + 8 + 8 + 64 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 1945638864.

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 35 ways as a sum of consecutive naturals, for example, 753127 + ... + 755705.

It is an arithmetic number, because the mean of its divisors is an integer number (33826208).

Almost surely, 2^1945638864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1945638864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3044358720).

1945638864 is an abundant number, since it is smaller than the sum of its proper divisors (4143078576).

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

1945638864 is a wasteful number, since it uses less digits than its factorization.

1945638864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2650 (or 2628 counting only the distinct ones).

The product of its digits is 4976640, while the sum is 54.

The square root of 1945638864 is about 44109.3965499416. The cubic root of 1945638864 is about 1248.4009128619.

The spelling of 1945638864 in words is "one billion, nine hundred forty-five million, six hundred thirty-eight thousand, eight hundred sixty-four".