52991440 has 80 divisors (see below), whose sum is σ = 127670400. Its totient is φ = 20445696.

The previous prime is 52991417. The next prime is 52991441. The reversal of 52991440 is 4419925.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 52991396 and 52991405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (52991441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 486106 + ... + 486214.

It is an arithmetic number, because the mean of its divisors is an integer number (1595880).

Almost surely, 2^52991440 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 52991440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (63835200).

52991440 is an abundant number, since it is smaller than the sum of its proper divisors (74678960).

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

52991440 is a wasteful number, since it uses less digits than its factorization.

52991440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 284 (or 278 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 52991440 is about 7279.5219623269. The cubic root of 52991440 is about 375.6083518138.

The spelling of 52991440 in words is "fifty-two million, nine hundred ninety-one thousand, four hundred forty".