51202215621 has 48 divisors (see below), whose sum is σ = 76611225600. Its totient is φ = 32934104064.

The previous prime is 51202215599. The next prime is 51202215667. The reversal of 51202215621 is 12651220215.

51202215621 is a `hidden beast` number, since 5 + 1 + 2 + 0 + 22 + 15 + 621 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-51202215621 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51202215121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 11035020 + ... + 11039658.

It is an arithmetic number, because the mean of its divisors is an integer number (1596067200).

Almost surely, 2^51202215621 is an apocalyptic number.

It is an amenable number.

51202215621 is a deficient number, since it is larger than the sum of its proper divisors (25409009979).

51202215621 is a wasteful number, since it uses less digits than its factorization.

51202215621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5058 (or 5055 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 27.

Adding to 51202215621 its reverse (12651220215), we get a palindrome (63853435836).

The spelling of 51202215621 in words is "fifty-one billion, two hundred two million, two hundred fifteen thousand, six hundred twenty-one".