51533221272 has 64 divisors (see below), whose sum is σ = 140414964480. Its totient is φ = 15665327232.

The previous prime is 51533221249. The next prime is 51533221279. The reversal of 51533221272 is 27212233515.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51533221279) 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 15 ways as a sum of consecutive naturals, for example, 969108 + ... + 1020899.

It is an arithmetic number, because the mean of its divisors is an integer number (2193983820).

Almost surely, 2^51533221272 is an apocalyptic number.

51533221272 is a gapful number since it is divisible by the number (52) formed by its first and last digit.

It is an amenable number.

51533221272 is an abundant number, since it is smaller than the sum of its proper divisors (88881743208).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51533221272 is a wasteful number, since it uses less digits than its factorization.

51533221272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1990112 (or 1990108 counting only the distinct ones).

The product of its digits is 25200, while the sum is 33.

Adding to 51533221272 its reverse (27212233515), we get a palindrome (78745454787).

The spelling of 51533221272 in words is "fifty-one billion, five hundred thirty-three million, two hundred twenty-one thousand, two hundred seventy-two".