64218623 has 4 divisors (see below), whose sum is σ = 73392720. Its totient is φ = 55044528.

The previous prime is 64218617. The next prime is 64218667. The reversal of 64218623 is 32681246.

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

It is not a de Polignac number, because 64218623 - 2⁴ = 64218607 is a prime.

It is a super-2 number, since 2×64218623² = 8248063080032258, 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 64218623.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64218023) 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, 4587038 + ... + 4587051.

It is an arithmetic number, because the mean of its divisors is an integer number (18348180).

Almost surely, 2^64218623 is an apocalyptic number.

64218623 is a deficient number, since it is larger than the sum of its proper divisors (9174097).

64218623 is an equidigital number, since it uses as much as digits as its factorization.

64218623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9174096.

The product of its digits is 13824, while the sum is 32.

The square root of 64218623 is about 8013.6522884388. The cubic root of 64218623 is about 400.4549469454.

Adding to 64218623 its reverse (32681246), we get a palindrome (96899869).

The spelling of 64218623 in words is "sixty-four million, two hundred eighteen thousand, six hundred twenty-three".