64144316381 has 4 divisors (see below), whose sum is σ = 64145704572. Its totient is φ = 64142928192.

The previous prime is 64144316371. The next prime is 64144316389. The reversal of 64144316381 is 18361344146.

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 45084028900 + 19060287481 = 212330^2 + 138059^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64144316381 is a prime.

It is a super-2 number, since 2×64144316381² (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 (64144316389) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 622310 + ... + 718023.

It is an arithmetic number, because the mean of its divisors is an integer number (16036426143).

Almost surely, 2^64144316381 is an apocalyptic number.

It is an amenable number.

64144316381 is a deficient number, since it is larger than the sum of its proper divisors (1388191).

64144316381 is a wasteful number, since it uses less digits than its factorization.

64144316381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1388190.

The product of its digits is 165888, while the sum is 41.

The spelling of 64144316381 in words is "sixty-four billion, one hundred forty-four million, three hundred sixteen thousand, three hundred eighty-one".