64115144021 has 4 divisors (see below), whose sum is σ = 64233656844. Its totient is φ = 63996631200.

The previous prime is 64115143999. The next prime is 64115144033. The reversal of 64115144021 is 12044151146.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 41430567025 + 22684576996 = 203545^2 + 150614^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64115144021 is a prime.

It is a super-2 number, since 2×64115144021² (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 (64115144221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 59255600 + ... + 59256681.

It is an arithmetic number, because the mean of its divisors is an integer number (16058414211).

Almost surely, 2^64115144021 is an apocalyptic number.

It is an amenable number.

64115144021 is a deficient number, since it is larger than the sum of its proper divisors (118512823).

64115144021 is a wasteful number, since it uses less digits than its factorization.

64115144021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118512822.

The product of its (nonzero) digits is 3840, while the sum is 29.

Adding to 64115144021 its reverse (12044151146), we get a palindrome (76159295167).

The spelling of 64115144021 in words is "sixty-four billion, one hundred fifteen million, one hundred forty-four thousand, twenty-one".