51106981590 has 320 divisors, whose sum is σ = 164928614400. Its totient is φ = 11108047104.

The previous prime is 51106981553. The next prime is 51106981637. The reversal of 51106981590 is 9518960115.

51106981590 is a `hidden beast` number, since 51 + 1 + 0 + 6 + 9 + 8 + 1 + 590 = 666.

It is a super-2 number, since 2×51106981590² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 11014491 + ... + 11019129.

It is an arithmetic number, because the mean of its divisors is an integer number (515401920).

Almost surely, 2^51106981590 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51106981590, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82464307200).

51106981590 is an abundant number, since it is smaller than the sum of its proper divisors (113821632810).

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

51106981590 is a wasteful number, since it uses less digits than its factorization.

51106981590 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4761 (or 4752 counting only the distinct ones).

The product of its (nonzero) digits is 97200, while the sum is 45.

The spelling of 51106981590 in words is "fifty-one billion, one hundred six million, nine hundred eighty-one thousand, five hundred ninety".