51136993 has 4 divisors (see below), whose sum is σ = 51196180. Its totient is φ = 51077808.

The previous prime is 51136991. The next prime is 51137033. The reversal of 51136993 is 39963115.

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

It can be written as a sum of positive squares in 2 ways, for example, as 34433424 + 16703569 = 5868^2 + 4087^2 .

It is a cyclic number.

It is not a de Polignac number, because 51136993 - 2¹ = 51136991 is a prime.

It is a super-2 number, since 2×51136993² = 5229984106164098, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51136991) 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 3 ways as a sum of consecutive naturals, for example, 28278 + ... + 30031.

It is an arithmetic number, because the mean of its divisors is an integer number (12799045).

Almost surely, 2^51136993 is an apocalyptic number.

It is an amenable number.

51136993 is a deficient number, since it is larger than the sum of its proper divisors (59187).

51136993 is an equidigital number, since it uses as much as digits as its factorization.

51136993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59186.

The product of its digits is 21870, while the sum is 37.

The square root of 51136993 is about 7151.0134246832. The cubic root of 51136993 is about 371.1747251087.

The spelling of 51136993 in words is "fifty-one million, one hundred thirty-six thousand, nine hundred ninety-three".