51891012 has 36 divisors (see below), whose sum is σ = 132018796. Its totient is φ = 17184960.

The previous prime is 51891011. The next prime is 51891017. The reversal of 51891012 is 21019815.

51891012 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 2 ways, for example, as 24265476 + 27625536 = 4926^2 + 5256^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51891011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1062 + ... + 10242.

Almost surely, 2^51891012 is an apocalyptic number.

It is an amenable number.

51891012 is an abundant number, since it is smaller than the sum of its proper divisors (80127784).

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

51891012 is a wasteful number, since it uses less digits than its factorization.

51891012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9348 (or 9343 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 27.

The square root of 51891012 is about 7203.5416289489. The cubic root of 51891012 is about 372.9901647434.

The spelling of 51891012 in words is "fifty-one million, eight hundred ninety-one thousand, twelve".