64979805869 has 24 divisors (see below), whose sum is σ = 75281293080. Its totient is φ = 55959263360.

The previous prime is 64979805829. The next prime is 64979805889. The reversal of 64979805869 is 96850897946.

It can be written as a sum of positive squares in 4 ways, for example, as 17264646025 + 47715159844 = 131395^2 + 218438^2 .

It is a de Polignac number, because none of the positive numbers 2^k-64979805869 is a prime.

It is a super-2 number, since 2×64979805869² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64979805829) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 11279 + ... + 360675.

It is an arithmetic number, because the mean of its divisors is an integer number (3136720545).

Almost surely, 2^64979805869 is an apocalyptic number.

It is an amenable number.

64979805869 is a deficient number, since it is larger than the sum of its proper divisors (10301487211).

64979805869 is a wasteful number, since it uses less digits than its factorization.

64979805869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 349501 (or 349490 counting only the distinct ones).

The product of its (nonzero) digits is 235146240, while the sum is 71.

The spelling of 64979805869 in words is "sixty-four billion, nine hundred seventy-nine million, eight hundred five thousand, eight hundred sixty-nine".