51438243 has 24 divisors (see below), whose sum is σ = 73876480. Its totient is φ = 31824000.

The previous prime is 51438229. The next prime is 51438271. The reversal of 51438243 is 34283415.

It is not a de Polignac number, because 51438243 - 2¹⁰ = 51437219 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51438243.

It is not an unprimeable number, because it can be changed into a prime (51438203) 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, 68118 + ... + 68868.

Almost surely, 2^51438243 is an apocalyptic number.

51438243 is a deficient number, since it is larger than the sum of its proper divisors (22438237).

51438243 is a wasteful number, since it uses less digits than its factorization.

51438243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 867 (or 850 counting only the distinct ones).

The product of its digits is 11520, while the sum is 30.

The square root of 51438243 is about 7172.0459424072. The cubic root of 51438243 is about 371.9021667228.

It can be divided in two parts, 51438 and 243, that added together give a triangular number (51681 = T₃₂₁).

The spelling of 51438243 in words is "fifty-one million, four hundred thirty-eight thousand, two hundred forty-three".