51315444 has 60 divisors (see below), whose sum is σ = 134896608. Its totient is φ = 17010000.

The previous prime is 51315437. The next prime is 51315449. The reversal of 51315444 is 44451315.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51315449) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 81009 + ... + 81639.

Almost surely, 2^51315444 is an apocalyptic number.

51315444 is a gapful number since it is divisible by the number (54) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51315444, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (67448304).

51315444 is an abundant number, since it is smaller than the sum of its proper divisors (83581164).

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

51315444 is a wasteful number, since it uses less digits than its factorization.

51315444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 898 (or 887 counting only the distinct ones).

The product of its digits is 4800, while the sum is 27.

The square root of 51315444 is about 7163.4798806167. The cubic root of 51315444 is about 371.6059823927.

Adding to 51315444 its reverse (44451315), we get a palindrome (95766759).

The spelling of 51315444 in words is "fifty-one million, three hundred fifteen thousand, four hundred forty-four".