65621623 has 4 divisors (see below), whose sum is σ = 65701800. Its totient is φ = 65541448.

The previous prime is 65621617. The next prime is 65621627. The reversal of 65621623 is 32612656.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65621623 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65621627) 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, 38848 + ... + 40501.

It is an arithmetic number, because the mean of its divisors is an integer number (16425450).

Almost surely, 2^65621623 is an apocalyptic number.

65621623 is a deficient number, since it is larger than the sum of its proper divisors (80177).

65621623 is an equidigital number, since it uses as much as digits as its factorization.

65621623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80176.

The product of its digits is 12960, while the sum is 31.

The square root of 65621623 is about 8100.7174373632. The cubic root of 65621623 is about 403.3502425957.

The spelling of 65621623 in words is "sixty-five million, six hundred twenty-one thousand, six hundred twenty-three".