64612081 has 4 divisors (see below), whose sum is σ = 65497252. Its totient is φ = 63726912.

The previous prime is 64612073. The next prime is 64612099. The reversal of 64612081 is 18021646.

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 19936225 + 44675856 = 4465^2 + 6684^2 .

It is a cyclic number.

It is not a de Polignac number, because 64612081 - 2³ = 64612073 is a prime.

It is a super-2 number, since 2×64612081² = 8349442022301122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64612001) 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 3 ways as a sum of consecutive naturals, for example, 442476 + ... + 442621.

It is an arithmetic number, because the mean of its divisors is an integer number (16374313).

Almost surely, 2^64612081 is an apocalyptic number.

It is an amenable number.

64612081 is a deficient number, since it is larger than the sum of its proper divisors (885171).

64612081 is an equidigital number, since it uses as much as digits as its factorization.

64612081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 885170.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 64612081 is about 8038.1640316679. The cubic root of 64612081 is about 401.2711250738.

The spelling of 64612081 in words is "sixty-four million, six hundred twelve thousand, eighty-one".