51436541857221 has 16 divisors (see below), whose sum is σ = 76205934777600. Its totient is φ = 34289385159744.

The previous prime is 51436541857189. The next prime is 51436541857291. The reversal of 51436541857221 is 12275814563415.

51436541857221 is a `hidden beast` number, since 5 + 1 + 4 + 3 + 6 + 5 + 41 + 8 + 572 + 21 = 666.

It is not a de Polignac number, because 51436541857221 - 2⁵ = 51436541857189 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51436541857291) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45057636 + ... + 46185101.

It is an arithmetic number, because the mean of its divisors is an integer number (4762870923600).

Almost surely, 2^{51436541857221} is an apocalyptic number.

It is an amenable number.

51436541857221 is a deficient number, since it is larger than the sum of its proper divisors (24769392920379).

51436541857221 is a wasteful number, since it uses less digits than its factorization.

51436541857221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91263625 (or 91263619 counting only the distinct ones).

The product of its digits is 8064000, while the sum is 54.

The spelling of 51436541857221 in words is "fifty-one trillion, four hundred thirty-six billion, five hundred forty-one million, eight hundred fifty-seven thousand, two hundred twenty-one".