51507242 has 4 divisors (see below), whose sum is σ = 77260866. Its totient is φ = 25753620.

The previous prime is 51507221. The next prime is 51507257. The reversal of 51507242 is 24270515.

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., 49014001 + 2493241 = 7001^2 + 1579^2 .

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 12876809 + ... + 12876812.

Almost surely, 2^51507242 is an apocalyptic number.

51507242 is a deficient number, since it is larger than the sum of its proper divisors (25753624).

51507242 is a wasteful number, since it uses less digits than its factorization.

51507242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25753623.

The product of its (nonzero) digits is 2800, while the sum is 26.

The square root of 51507242 is about 7176.8546035154. The cubic root of 51507242 is about 372.0683816559.

Adding to 51507242 its reverse (24270515), we get a palindrome (75777757).

The spelling of 51507242 in words is "fifty-one million, five hundred seven thousand, two hundred forty-two".