51111900 has 324 divisors, whose sum is σ = 199388280. Its totient is φ = 10886400.

The previous prime is 51111869. The next prime is 51111937. The reversal of 51111900 is 911115.

It is a super-2 number, since 2×51111900² = 5224852643220000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 837870 + ... + 837930.

Almost surely, 2^51111900 is an apocalyptic number.

51111900 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 51111900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99694140).

51111900 is an abundant number, since it is smaller than the sum of its proper divisors (148276380).

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

51111900 is a wasteful number, since it uses less digits than its factorization.

51111900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114 (or 97 counting only the distinct ones).

The product of its (nonzero) digits is 45, while the sum is 18.

The square root of 51111900 is about 7149.2587028307. The cubic root of 51111900 is about 371.1140031753.

The spelling of 51111900 in words is "fifty-one million, one hundred eleven thousand, nine hundred".