64987947321 has 32 divisors (see below), whose sum is σ = 100110117888. Its totient is φ = 37111842240.

The previous prime is 64987947319. The next prime is 64987947337. The reversal of 64987947321 is 12374978946.

It is not a de Polignac number, because 64987947321 - 2¹ = 64987947319 is a prime.

It is not an unprimeable number, because it can be changed into a prime (64987947341) 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 31 ways as a sum of consecutive naturals, for example, 588126 + ... + 689831.

It is an arithmetic number, because the mean of its divisors is an integer number (3128441184).

Almost surely, 2^64987947321 is an apocalyptic number.

It is an amenable number.

64987947321 is a deficient number, since it is larger than the sum of its proper divisors (35122170567).

64987947321 is a wasteful number, since it uses less digits than its factorization.

64987947321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1278061.

The product of its digits is 18289152, while the sum is 60.

The spelling of 64987947321 in words is "sixty-four billion, nine hundred eighty-seven million, nine hundred forty-seven thousand, three hundred twenty-one".