51643623 has 8 divisors (see below), whose sum is σ = 69540336. Its totient is φ = 34088000.

The previous prime is 51643609. The next prime is 51643633. The reversal of 51643623 is 32634615.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 51643623 - 2⁴ = 51643607 is a prime.

It is a super-2 number, since 2×51643623² = 5334127593132258, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51643633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 84918 + ... + 85523.

It is an arithmetic number, because the mean of its divisors is an integer number (8692542).

Almost surely, 2^51643623 is an apocalyptic number.

51643623 is a deficient number, since it is larger than the sum of its proper divisors (17896713).

51643623 is a wasteful number, since it uses less digits than its factorization.

51643623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170545.

The product of its digits is 12960, while the sum is 30.

The square root of 51643623 is about 7186.3497688326. The cubic root of 51643623 is about 372.3964800999.

The spelling of 51643623 in words is "fifty-one million, six hundred forty-three thousand, six hundred twenty-three".