51538042 has 4 divisors (see below), whose sum is σ = 77307066. Its totient is φ = 25769020.

The previous prime is 51538021. The next prime is 51538043. The reversal of 51538042 is 24083515.

It is a Cunningham number, because it is equal to 7179²+1.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 51538041 + 1 = 7179^2 + 1^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 51538042.

It is not an unprimeable number, because it can be changed into a prime (51538043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12884509 + ... + 12884512.

Almost surely, 2^51538042 is an apocalyptic number.

51538042 is a deficient number, since it is larger than the sum of its proper divisors (25769024).

51538042 is a wasteful number, since it uses less digits than its factorization.

51538042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25769023.

The product of its (nonzero) digits is 4800, while the sum is 28.

The square root of 51538042 is about 7179.0000696476. Note that the first 4 decimals coincide. The cubic root of 51538042 is about 372.1425293049.

The spelling of 51538042 in words is "fifty-one million, five hundred thirty-eight thousand, forty-two".