51420551121 has 27 divisors (see below), whose sum is σ = 74975375163. Its totient is φ = 33959727360.

The previous prime is 51420551111. The next prime is 51420551123. The reversal of 51420551121 is 12115502415.

It is a happy number.

The square root of 51420551121 is 226761.

It is a perfect power (a square), and thus also a powerful number.

51420551121 is a `hidden beast` number, since 5 + 142 + 0 + 5 + 511 + 2 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 51064700625 + 355850496 = 225975^2 + 18864^2 .

It is not a de Polignac number, because 51420551121 - 2²³ = 51412162513 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (51420551123) 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 26 ways as a sum of consecutive naturals, for example, 89116785 + ... + 89117361.

Almost surely, 2^51420551121 is an apocalyptic number.

51420551121 is the 226761-st square number.

51420551121 is the 113381-st centered octagonal number.

It is an amenable number.

51420551121 is a deficient number, since it is larger than the sum of its proper divisors (23554824042).

51420551121 is an frugal number, since it uses more digits than its factorization.

51420551121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1422 (or 711 counting only the distinct ones).

The product of its (nonzero) digits is 2000, while the sum is 27.

The spelling of 51420551121 in words is "fifty-one billion, four hundred twenty million, five hundred fifty-one thousand, one hundred twenty-one".