51389240 has 96 divisors (see below), whose sum is σ = 136170720. Its totient is φ = 17402112.

The previous prime is 51389231. The next prime is 51389251. The reversal of 51389240 is 4298315.

It is a junction number, because it is equal to n+sod(n) for n = 51389197 and 51389206.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 307637 + ... + 307803.

It is an arithmetic number, because the mean of its divisors is an integer number (1418445).

Almost surely, 2^51389240 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 51389240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (68085360).

51389240 is an abundant number, since it is smaller than the sum of its proper divisors (84781480).

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

51389240 is a wasteful number, since it uses less digits than its factorization.

51389240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 349 (or 338 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 51389240 is about 7168.6288786629. The cubic root of 51389240 is about 371.7840308052.

The spelling of 51389240 in words is "fifty-one million, three hundred eighty-nine thousand, two hundred forty".