51209540090 has 32 divisors (see below), whose sum is σ = 95374676880. Its totient is φ = 19773540864.

The previous prime is 51209540059. The next prime is 51209540111. The reversal of 51209540090 is 9004590215.

It can be written as a sum of positive squares in 8 ways, for example, as 41756061649 + 9453478441 = 204343^2 + 97229^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 51209540090.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1746632 + ... + 1775708.

Almost surely, 2^51209540090 is an apocalyptic number.

51209540090 is a deficient number, since it is larger than the sum of its proper divisors (44165136790).

51209540090 is a wasteful number, since it uses less digits than its factorization.

51209540090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35186.

The product of its (nonzero) digits is 16200, while the sum is 35.

The spelling of 51209540090 in words is "fifty-one billion, two hundred nine million, five hundred forty thousand, ninety".