51451121161 has 4 divisors (see below), whose sum is σ = 56128495824. Its totient is φ = 46773746500.

The previous prime is 51451121119. The next prime is 51451121213. The reversal of 51451121161 is 16112115415.

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 51451121161 - 2¹⁵ = 51451088393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51451121101) 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, 2338687315 + ... + 2338687336.

It is an arithmetic number, because the mean of its divisors is an integer number (14032123956).

Almost surely, 2^51451121161 is an apocalyptic number.

It is an amenable number.

51451121161 is a deficient number, since it is larger than the sum of its proper divisors (4677374663).

51451121161 is a wasteful number, since it uses less digits than its factorization.

51451121161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4677374662.

The product of its digits is 1200, while the sum is 28.

Adding to 51451121161 its reverse (16112115415), we get a palindrome (67563236576).

The spelling of 51451121161 in words is "fifty-one billion, four hundred fifty-one million, one hundred twenty-one thousand, one hundred sixty-one".