51281622 has 96 divisors (see below), whose sum is σ = 136468800. Its totient is φ = 13584384.

The previous prime is 51281621. The next prime is 51281683. The reversal of 51281622 is 22618215.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51281621) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 190504 + ... + 190772.

It is an arithmetic number, because the mean of its divisors is an integer number (1421550).

Almost surely, 2^51281622 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51281622, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (68234400).

51281622 is an abundant number, since it is smaller than the sum of its proper divisors (85187178).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51281622 is a wasteful number, since it uses less digits than its factorization.

51281622 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 390 (or 387 counting only the distinct ones).

The product of its digits is 1920, while the sum is 27.

The square root of 51281622 is about 7161.1187673435. The cubic root of 51281622 is about 371.5243226372.

Adding to 51281622 its reverse (22618215), we get a palindrome (73899837).

The spelling of 51281622 in words is "fifty-one million, two hundred eighty-one thousand, six hundred twenty-two".