51645923 has 4 divisors (see below), whose sum is σ = 59023920. Its totient is φ = 44267928.

The previous prime is 51645911. The next prime is 51645931. The reversal of 51645923 is 32954615.

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 51645923 - 2¹⁰ = 51644899 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51645943) 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, 3688988 + ... + 3689001.

It is an arithmetic number, because the mean of its divisors is an integer number (14755980).

Almost surely, 2^51645923 is an apocalyptic number.

51645923 is a deficient number, since it is larger than the sum of its proper divisors (7377997).

51645923 is an equidigital number, since it uses as much as digits as its factorization.

51645923 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7377996.

The product of its digits is 32400, while the sum is 35.

The square root of 51645923 is about 7186.5097926601. The cubic root of 51645923 is about 372.4020083667.

The spelling of 51645923 in words is "fifty-one million, six hundred forty-five thousand, nine hundred twenty-three".