51172993 has 8 divisors (see below), whose sum is σ = 51840360. Its totient is φ = 50509440.

The previous prime is 51172987. The next prime is 51172997. The reversal of 51172993 is 39927115.

It can be written as a sum of positive squares in 4 ways, for example, as 1723969 + 49449024 = 1313^2 + 7032^2 .

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 51172993 - 2⁹ = 51172481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51172997) 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, 33813 + ... + 35293.

It is an arithmetic number, because the mean of its divisors is an integer number (6480045).

Almost surely, 2^51172993 is an apocalyptic number.

It is an amenable number.

51172993 is a deficient number, since it is larger than the sum of its proper divisors (667367).

51172993 is a wasteful number, since it uses less digits than its factorization.

51172993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1907.

The product of its digits is 17010, while the sum is 37.

The square root of 51172993 is about 7153.5301075763. The cubic root of 51172993 is about 371.2618059406.

The spelling of 51172993 in words is "fifty-one million, one hundred seventy-two thousand, nine hundred ninety-three".