64636081 has 4 divisors (see below), whose sum is σ = 68038000. Its totient is φ = 61234164.

The previous prime is 64636079. The next prime is 64636109. The reversal of 64636081 is 18063646.

64636081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 64636081 - 2¹ = 64636079 is a prime.

It is a super-2 number, since 2×64636081² = 8355645934077122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64636021) 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 3 ways as a sum of consecutive naturals, for example, 1700931 + ... + 1700968.

It is an arithmetic number, because the mean of its divisors is an integer number (17009500).

Almost surely, 2^64636081 is an apocalyptic number.

It is an amenable number.

64636081 is a deficient number, since it is larger than the sum of its proper divisors (3401919).

64636081 is a wasteful number, since it uses less digits than its factorization.

64636081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3401918.

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 64636081 is about 8039.6567712807. The cubic root of 64636081 is about 401.3208026505.

It can be divided in two parts, 6463 and 6081, that added together give a square (12544 = 112²).

The spelling of 64636081 in words is "sixty-four million, six hundred thirty-six thousand, eighty-one".