51090917089 has 27 divisors (see below), whose sum is σ = 54184657611. Its totient is φ = 48172152960.

The previous prime is 51090917081. The next prime is 51090917099. The reversal of 51090917089 is 98071909015.

It is a happy number.

The square root of 51090917089 is 226033.

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

It can be written as a sum of positive squares in 13 ways, for example, as 48195616225 + 2895300864 = 219535^2 + 53808^2 .

It is not a de Polignac number, because 51090917089 - 2³ = 51090917081 is a prime.

It is a super-2 number, since 2×51090917089² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51090917081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 342891987 + ... + 342892135.

Almost surely, 2^51090917089 is an apocalyptic number.

51090917089 is the 226033-rd square number.

51090917089 is the 113017-th centered octagonal number.

It is an amenable number.

51090917089 is a deficient number, since it is larger than the sum of its proper divisors (3093740522).

51090917089 is an frugal number, since it uses more digits than its factorization.

51090917089 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 454 (or 227 counting only the distinct ones).

The product of its (nonzero) digits is 204120, while the sum is 49.

Multiplying 51090917089 by its sum of digits (49), we get a square (2503454937361 = 1582231²).

The spelling of 51090917089 in words is "fifty-one billion, ninety million, nine hundred seventeen thousand, eighty-nine".