51111323213 has 4 divisors (see below), whose sum is σ = 51113603520. Its totient is φ = 51109042908.

The previous prime is 51111323183. The next prime is 51111323273. The reversal of 51111323213 is 31232311115.

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 51111323213 - 2³² = 46816355917 is a prime.

It is a super-2 number, since 2×51111323213² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51111323273) 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, 1106195 + ... + 1151472.

It is an arithmetic number, because the mean of its divisors is an integer number (12778400880).

Almost surely, 2^51111323213 is an apocalyptic number.

It is an amenable number.

51111323213 is a deficient number, since it is larger than the sum of its proper divisors (2280307).

51111323213 is a wasteful number, since it uses less digits than its factorization.

51111323213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2280306.

The product of its digits is 540, while the sum is 23.

Adding to 51111323213 its reverse (31232311115), we get a palindrome (82343634328).

The spelling of 51111323213 in words is "fifty-one billion, one hundred eleven million, three hundred twenty-three thousand, two hundred thirteen".