51081300 has 72 divisors (see below), whose sum is σ = 164225600. Its totient is φ = 13620960.

The previous prime is 51081299. The next prime is 51081301. The reversal of 51081300 is 318015.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (51081299) and next prime (51081301).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51081301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6760 + ... + 12159.

Almost surely, 2^51081300 is an apocalyptic number.

51081300 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

51081300 is an abundant number, since it is smaller than the sum of its proper divisors (113144300).

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

51081300 is a wasteful number, since it uses less digits than its factorization.

51081300 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18942 (or 18929 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 18.

The square root of 51081300 is about 7147.1183004061. The cubic root of 51081300 is about 371.0399280872.

Adding to 51081300 its reverse (318015), we get a palindrome (51399315).

It can be divided in two parts, 510 and 81300, that added together give a triangular number (81810 = T₄₀₄).

The spelling of 51081300 in words is "fifty-one million, eighty-one thousand, three hundred".