64387785639999 has 16 divisors (see below), whose sum is σ = 85913525973600. Its totient is φ = 42893628589056.

The previous prime is 64387785639997. The next prime is 64387785640111. The reversal of 64387785639999 is 99993658778346.

It is a Cunningham number, because it is equal to 8024200²-1.

It is not a de Polignac number, because 64387785639999 - 2¹ = 64387785639997 is a prime.

It is a super-2 number, since 2×64387785639999² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64387785639997) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22735237 + ... + 25409969.

It is an arithmetic number, because the mean of its divisors is an integer number (5369595373350).

Almost surely, 2^{64387785639999} is an apocalyptic number.

64387785639999 is a deficient number, since it is larger than the sum of its proper divisors (21525740333601).

64387785639999 is a wasteful number, since it uses less digits than its factorization.

64387785639999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2680634.

The product of its digits is 133327918080, while the sum is 93.

The spelling of 64387785639999 in words is "sixty-four trillion, three hundred eighty-seven billion, seven hundred eighty-five million, six hundred thirty-nine thousand, nine hundred ninety-nine".