51143820 has 384 divisors, whose sum is σ = 203212800. Its totient is φ = 9289728.

The previous prime is 51143797. The next prime is 51143821. The reversal of 51143820 is 2834115.

It is not an unprimeable number, because it can be changed into a prime (51143821) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1763566 + ... + 1763594.

It is an arithmetic number, because the mean of its divisors is an integer number (529200).

Almost surely, 2^51143820 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 51143820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101606400).

51143820 is an abundant number, since it is smaller than the sum of its proper divisors (152068980).

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

51143820 is a wasteful number, since it uses less digits than its factorization.

51143820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97 (or 95 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 51143820 is about 7151.4907536821. The cubic root of 51143820 is about 371.1912421605.

Adding to 51143820 its reverse (2834115), we get a palindrome (53977935).

The spelling of 51143820 in words is "fifty-one million, one hundred forty-three thousand, eight hundred twenty".