64881693 has 24 divisors (see below), whose sum is σ = 95519736. Its totient is φ = 42432000.

The previous prime is 64881679. The next prime is 64881701. The reversal of 64881693 is 39618846.

64881693 is a `hidden beast` number, since 6 + 488 + 169 + 3 = 666.

64881693 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 21874329 + 43007364 = 4677^2 + 6558^2 .

It is not a de Polignac number, because 64881693 - 2⁶ = 64881629 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64881653) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 124273 + ... + 124793.

It is an arithmetic number, because the mean of its divisors is an integer number (3979989).

Almost surely, 2^64881693 is an apocalyptic number.

It is an amenable number.

64881693 is a deficient number, since it is larger than the sum of its proper divisors (30638043).

64881693 is a wasteful number, since it uses less digits than its factorization.

64881693 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 765 (or 762 counting only the distinct ones).

The product of its digits is 248832, while the sum is 45.

The square root of 64881693 is about 8054.9173180114. The cubic root of 64881693 is about 401.8284892483.

The spelling of 64881693 in words is "sixty-four million, eight hundred eighty-one thousand, six hundred ninety-three".