51644233251161 has 4 divisors (see below), whose sum is σ = 51644368024500. Its totient is φ = 51644098477824.

The previous prime is 51644233251101. The next prime is 51644233251197. The reversal of 51644233251161 is 16115233244615.

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 33078820513561 + 18565412737600 = 5751419^2 + 4308760^2 .

It is a cyclic number.

It is not a de Polignac number, because 51644233251161 - 2⁶ = 51644233251097 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (51644233251101) 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, 66810236 + ... + 67578813.

It is an arithmetic number, because the mean of its divisors is an integer number (12911092006125).

Almost surely, 2^{51644233251161} is an apocalyptic number.

It is an amenable number.

51644233251161 is a deficient number, since it is larger than the sum of its proper divisors (134773339).

51644233251161 is a wasteful number, since it uses less digits than its factorization.

51644233251161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134773338.

The product of its digits is 518400, while the sum is 44.

Adding to 51644233251161 its reverse (16115233244615), we get a palindrome (67759466495776).

The spelling of 51644233251161 in words is "fifty-one trillion, six hundred forty-four billion, two hundred thirty-three million, two hundred fifty-one thousand, one hundred sixty-one".