64912765015805 has 18 divisors (see below), whose sum is σ = 90613096999866. Its totient is φ = 44511523821408.

The previous prime is 64912765015739. The next prime is 64912765015811. The reversal of 64912765015805 is 50851056721946.

It can be written as a sum of positive squares in 3 ways, for example, as 31158210458116 + 33754554557689 = 5581954^2 + 5809867^2 .

It is not a de Polignac number, because 64912765015805 - 2¹² = 64912765011709 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 125852219 + ... + 126366951.

It is an arithmetic number, because the mean of its divisors is an integer number (5034060944437).

Almost surely, 2^{64912765015805} is an apocalyptic number.

It is an amenable number.

64912765015805 is a deficient number, since it is larger than the sum of its proper divisors (25700331984061).

64912765015805 is an frugal number, since it uses more digits than its factorization.

64912765015805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1029485 (or 514745 counting only the distinct ones).

The product of its (nonzero) digits is 18144000, while the sum is 59.

The spelling of 64912765015805 in words is "sixty-four trillion, nine hundred twelve billion, seven hundred sixty-five million, fifteen thousand, eight hundred five".