51202440 has 96 divisors (see below), whose sum is σ = 170515800. Its totient is φ = 13317120.

The previous prime is 51202387. The next prime is 51202471. The reversal of 51202440 is 4420215.

It can be written as a sum of positive squares in 4 ways, for example, as 12489156 + 38713284 = 3534^2 + 6222^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13026 + ... + 16494.

Almost surely, 2^51202440 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51202440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (85257900).

51202440 is an abundant number, since it is smaller than the sum of its proper divisors (119313360).

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

51202440 is a wasteful number, since it uses less digits than its factorization.

51202440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3527 (or 3520 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 51202440 is about 7155.5880261513. The cubic root of 51202440 is about 371.3330052811. Note that the first 3 decimals are identical.

Adding to 51202440 its reverse (4420215), we get a palindrome (55622655).

The spelling of 51202440 in words is "fifty-one million, two hundred two thousand, four hundred forty".