51111321000 has 128 divisors (see below), whose sum is σ = 160538976000. Its totient is φ = 13538092800.

The previous prime is 51111320993. The next prime is 51111321029. The reversal of 51111321000 is 12311115.

It is a super-2 number, since 2×51111321000² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 389829 + ... + 504171.

It is an arithmetic number, because the mean of its divisors is an integer number (1254210750).

Almost surely, 2^51111321000 is an apocalyptic number.

51111321000 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51111321000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80269488000).

51111321000 is an abundant number, since it is smaller than the sum of its proper divisors (109427655000).

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

51111321000 is a wasteful number, since it uses less digits than its factorization.

51111321000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114516 (or 114502 counting only the distinct ones).

The product of its (nonzero) digits is 30, while the sum is 15.

Adding to 51111321000 its reverse (12311115), we get a palindrome (51123632115).

The spelling of 51111321000 in words is "fifty-one billion, one hundred eleven million, three hundred twenty-one thousand".