51111120 has 80 divisors (see below), whose sum is σ = 159489792. Its totient is φ = 13539840.

The previous prime is 51111119. The next prime is 51111139. The reversal of 51111120 is 2111115.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×51111120² = 5224693175308800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 51111096 and 51111105.

It is a congruent number.

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, 40905 + ... + 42135.

Almost surely, 2^51111120 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51111120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (79744896).

51111120 is an abundant number, since it is smaller than the sum of its proper divisors (108378672).

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

51111120 is a wasteful number, since it uses less digits than its factorization.

51111120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1420 (or 1414 counting only the distinct ones).

The product of its (nonzero) digits is 10, while the sum is 12.

The square root of 51111120 is about 7149.2041515123. The cubic root of 51111120 is about 371.1121153541.

Adding to 51111120 its reverse (2111115), we get a palindrome (53222235).

The spelling of 51111120 in words is "fifty-one million, one hundred eleven thousand, one hundred twenty".