51891295690 has 16 divisors (see below), whose sum is σ = 100589281128. Its totient is φ = 19159862976.

The previous prime is 51891295679. The next prime is 51891295721. The reversal of 51891295690 is 9659219815.

51891295690 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 19827737721 + 32063557969 = 140811^2 + 179063^2 .

It is a super-2 number, since 2×51891295690² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 199581777 + ... + 199582036.

Almost surely, 2^51891295690 is an apocalyptic number.

51891295690 is a deficient number, since it is larger than the sum of its proper divisors (48697985438).

51891295690 is a wasteful number, since it uses less digits than its factorization.

51891295690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 399163833.

The product of its (nonzero) digits is 1749600, while the sum is 55.

The spelling of 51891295690 in words is "fifty-one billion, eight hundred ninety-one million, two hundred ninety-five thousand, six hundred ninety".