51911513 has 4 divisors (see below), whose sum is σ = 51969408. Its totient is φ = 51853620.

The previous prime is 51911491. The next prime is 51911521. The reversal of 51911513 is 31511915.

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.

It is a cyclic number.

It is not a de Polignac number, because 51911513 - 2⁸ = 51911257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51911543) 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, 27581 + ... + 29402.

It is an arithmetic number, because the mean of its divisors is an integer number (12992352).

Almost surely, 2^51911513 is an apocalyptic number.

It is an amenable number.

51911513 is a deficient number, since it is larger than the sum of its proper divisors (57895).

51911513 is an equidigital number, since it uses as much as digits as its factorization.

51911513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57894.

The product of its digits is 675, while the sum is 26.

The square root of 51911513 is about 7204.9644690311. The cubic root of 51911513 is about 373.0392783521.

The spelling of 51911513 in words is "fifty-one million, nine hundred eleven thousand, five hundred thirteen".