64918643 has 4 divisors (see below), whose sum is σ = 64992720. Its totient is φ = 64844568.

The previous prime is 64918589. The next prime is 64918663. The reversal of 64918643 is 34681946.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 64918643 - 2¹² = 64914547 is a prime.

It is a super-2 number, since 2×64918643² = 8428860417922898, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 64918643.

It is not an unprimeable number, because it can be changed into a prime (64918663) 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, 35708 + ... + 37481.

It is an arithmetic number, because the mean of its divisors is an integer number (16248180).

Almost surely, 2^64918643 is an apocalyptic number.

64918643 is a deficient number, since it is larger than the sum of its proper divisors (74077).

64918643 is an equidigital number, since it uses as much as digits as its factorization.

64918643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74076.

The product of its digits is 124416, while the sum is 41.

The square root of 64918643 is about 8057.2106215489. The cubic root of 64918643 is about 401.9047549576.

The spelling of 64918643 in words is "sixty-four million, nine hundred eighteen thousand, six hundred forty-three".