64644653 has 4 divisors (see below), whose sum is σ = 64663068. Its totient is φ = 64626240.

The previous prime is 64644649. The next prime is 64644677. The reversal of 64644653 is 35644646.

It is a happy number.

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 55323844 + 9320809 = 7438^2 + 3053^2 .

It is a cyclic number.

It is not a de Polignac number, because 64644653 - 2² = 64644649 is a prime.

It is a super-2 number, since 2×64644653² = 8357862322980818, which 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 (64641653) 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, 2126 + ... + 11567.

It is an arithmetic number, because the mean of its divisors is an integer number (16165767).

Almost surely, 2^64644653 is an apocalyptic number.

It is an amenable number.

64644653 is a deficient number, since it is larger than the sum of its proper divisors (18415).

64644653 is a wasteful number, since it uses less digits than its factorization.

64644653 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18414.

The product of its digits is 207360, while the sum is 38.

The square root of 64644653 is about 8040.1898609423. The cubic root of 64644653 is about 401.3385428446.

The spelling of 64644653 in words is "sixty-four million, six hundred forty-four thousand, six hundred fifty-three".