64813669 has 4 divisors (see below), whose sum is σ = 64852396. Its totient is φ = 64774944.

The previous prime is 64813663. The next prime is 64813711. The reversal of 64813669 is 96631846.

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 6061444 + 58752225 = 2462^2 + 7665^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64813669 is a prime.

It is a super-2 number, since 2×64813669² = 8401623378483122, 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 (64813663) 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, 16734 + ... + 20239.

It is an arithmetic number, because the mean of its divisors is an integer number (16213099).

Almost surely, 2^64813669 is an apocalyptic number.

It is an amenable number.

64813669 is a deficient number, since it is larger than the sum of its proper divisors (38727).

64813669 is a wasteful number, since it uses less digits than its factorization.

64813669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38726.

The product of its digits is 186624, while the sum is 43.

The square root of 64813669 is about 8050.6936968189. The cubic root of 64813669 is about 401.6880102828.

The spelling of 64813669 in words is "sixty-four million, eight hundred thirteen thousand, six hundred sixty-nine".