51000013 has 4 divisors (see below), whose sum is σ = 51864480. Its totient is φ = 50135548.

The previous prime is 50999999. The next prime is 51000041. The reversal of 51000013 is 31000015.

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: 31000015 = 5 ⋅6200003.

It is a cyclic number.

It is not a de Polignac number, because 51000013 - 2¹³ = 50991821 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51000083) 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, 432145 + ... + 432262.

It is an arithmetic number, because the mean of its divisors is an integer number (12966120).

Almost surely, 2^51000013 is an apocalyptic number.

It is an amenable number.

51000013 is a deficient number, since it is larger than the sum of its proper divisors (864467).

51000013 is an equidigital number, since it uses as much as digits as its factorization.

51000013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 864466.

The product of its (nonzero) digits is 15, while the sum is 10.

The square root of 51000013 is about 7141.4293387248. The cubic root of 51000013 is about 370.8430084362.

Adding to 51000013 its reverse (31000015), we get a palindrome (82000028).

The spelling of 51000013 in words is "fifty-one million, thirteen", and thus it is an aban number and an uban number.