51244220 has 24 divisors (see below), whose sum is σ = 107946384. Its totient is φ = 20434176.

The previous prime is 51244217. The next prime is 51244243. The reversal of 51244220 is 2244215.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 51244192 and 51244201.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2939 + ... + 10541.

It is an arithmetic number, because the mean of its divisors is an integer number (4497766).

Almost surely, 2^51244220 is an apocalyptic number.

It is an amenable number.

51244220 is an abundant number, since it is smaller than the sum of its proper divisors (56702164).

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

51244220 is a wasteful number, since it uses less digits than its factorization.

51244220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7949 (or 7947 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 51244220 is about 7158.5068275444. The cubic root of 51244220 is about 371.4339775206.

Adding to 51244220 its reverse (2244215), we get a palindrome (53488435).

The spelling of 51244220 in words is "fifty-one million, two hundred forty-four thousand, two hundred twenty".