51766101221 has 4 divisors (see below), whose sum is σ = 52268684832. Its totient is φ = 51263517612.

The previous prime is 51766101151. The next prime is 51766101241. The reversal of 51766101221 is 12210166715.

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 51766101221 - 2¹⁴ = 51766084837 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51766101241) 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, 251291651 + ... + 251291856.

It is an arithmetic number, because the mean of its divisors is an integer number (13067171208).

Almost surely, 2^51766101221 is an apocalyptic number.

It is an amenable number.

51766101221 is a deficient number, since it is larger than the sum of its proper divisors (502583611).

51766101221 is a wasteful number, since it uses less digits than its factorization.

51766101221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 502583610.

The product of its (nonzero) digits is 5040, while the sum is 32.

Adding to 51766101221 its reverse (12210166715), we get a palindrome (63976267936).

The spelling of 51766101221 in words is "fifty-one billion, seven hundred sixty-six million, one hundred one thousand, two hundred twenty-one".