51981424 has 40 divisors (see below), whose sum is σ = 110385792. Its totient is φ = 23517120.

The previous prime is 51981407. The next prime is 51981431. The reversal of 51981424 is 42418915.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 51981424.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 45727 + ... + 46849.

Almost surely, 2^51981424 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 51981424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (55192896).

51981424 is an abundant number, since it is smaller than the sum of its proper divisors (58404368).

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

51981424 is a wasteful number, since it uses less digits than its factorization.

51981424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1405 (or 1399 counting only the distinct ones).

The product of its digits is 11520, while the sum is 34.

The square root of 51981424 is about 7209.8144220222. The cubic root of 51981424 is about 373.2066647938.

The spelling of 51981424 in words is "fifty-one million, nine hundred eighty-one thousand, four hundred twenty-four".