51009120 has 72 divisors (see below), whose sum is σ = 174073536. Its totient is φ = 13602048.

The previous prime is 51009097. The next prime is 51009121. The reversal of 51009120 is 2190015.

It is a tau number, because it is divible by the number of its divisors (72).

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

It is a junction number, because it is equal to n+sod(n) for n = 51009093 and 51009102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51009121) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16272 + ... + 19151.

It is an arithmetic number, because the mean of its divisors is an integer number (2417688).

Almost surely, 2^51009120 is an apocalyptic number.

It is an amenable number.

51009120 is an abundant number, since it is smaller than the sum of its proper divisors (123064416).

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

51009120 is a wasteful number, since it uses less digits than its factorization.

51009120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35444 (or 35433 counting only the distinct ones).

The product of its (nonzero) digits is 90, while the sum is 18.

The square root of 51009120 is about 7142.0669277178. The cubic root of 51009120 is about 370.8650807591.

Adding to 51009120 its reverse (2190015), we get a palindrome (53199135).

The spelling of 51009120 in words is "fifty-one million, nine thousand, one hundred twenty".