51281630 has 16 divisors (see below), whose sum is σ = 94802400. Its totient is φ = 19958112.

The previous prime is 51281621. The next prime is 51281683. The reversal of 51281630 is 3618215.

It is a self number, because there is not a number n which added to its sum of digits gives 51281630.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 68930 + ... + 69669.

It is an arithmetic number, because the mean of its divisors is an integer number (5925150).

Almost surely, 2^51281630 is an apocalyptic number.

51281630 is a deficient number, since it is larger than the sum of its proper divisors (43520770).

51281630 is a wasteful number, since it uses less digits than its factorization.

51281630 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138643.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 51281630 is about 7161.1193259155. The cubic root of 51281630 is about 371.5243419566.

Adding to 51281630 its reverse (3618215), we get a palindrome (54899845).

The spelling of 51281630 in words is "fifty-one million, two hundred eighty-one thousand, six hundred thirty".