51438399 has 16 divisors (see below), whose sum is σ = 70895232. Its totient is φ = 33149088.

The previous prime is 51438397. The next prime is 51438403. The reversal of 51438399 is 99383415.

It is not a de Polignac number, because 51438399 - 2¹ = 51438397 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 51438399.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51438397) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16672 + ... + 19514.

It is an arithmetic number, because the mean of its divisors is an integer number (4430952).

Almost surely, 2^51438399 is an apocalyptic number.

51438399 is a deficient number, since it is larger than the sum of its proper divisors (19456833).

51438399 is a wasteful number, since it uses less digits than its factorization.

51438399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3046.

The product of its digits is 116640, while the sum is 42.

The square root of 51438399 is about 7172.0568179568. The cubic root of 51438399 is about 371.9025426861.

The spelling of 51438399 in words is "fifty-one million, four hundred thirty-eight thousand, three hundred ninety-nine".