51725731281221 has 32 divisors (see below), whose sum is σ = 54980151045120. Its totient is φ = 48576947328000.

The previous prime is 51725731281187. The next prime is 51725731281223. The reversal of 51725731281221 is 12218213752715.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51725731281221 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 (51725731281223) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 530890916 + ... + 530988338.

It is an arithmetic number, because the mean of its divisors is an integer number (1718129720160).

Almost surely, 2^{51725731281221} is an apocalyptic number.

It is an amenable number.

51725731281221 is a deficient number, since it is larger than the sum of its proper divisors (3254419763899).

51725731281221 is a wasteful number, since it uses less digits than its factorization.

51725731281221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98837.

The product of its digits is 470400, while the sum is 47.

The spelling of 51725731281221 in words is "fifty-one trillion, seven hundred twenty-five billion, seven hundred thirty-one million, two hundred eighty-one thousand, two hundred twenty-one".