51661873 has 4 divisors (see below), whose sum is σ = 51906928. Its totient is φ = 51416820.

The previous prime is 51661867. The next prime is 51661889. The reversal of 51661873 is 37816615.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 37816615 = 5 ⋅7563323.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51661873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51661843) 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, 122211 + ... + 122632.

It is an arithmetic number, because the mean of its divisors is an integer number (12976732).

Almost surely, 2^51661873 is an apocalyptic number.

It is an amenable number.

51661873 is a deficient number, since it is larger than the sum of its proper divisors (245055).

51661873 is a wasteful number, since it uses less digits than its factorization.

51661873 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245054.

The product of its digits is 30240, while the sum is 37.

The square root of 51661873 is about 7187.6194250948. The cubic root of 51661873 is about 372.4403411806.

The spelling of 51661873 in words is "fifty-one million, six hundred sixty-one thousand, eight hundred seventy-three".