51690144 has 96 divisors (see below), whose sum is σ = 152893440. Its totient is φ = 15148800.

The previous prime is 51690097. The next prime is 51690173. The reversal of 51690144 is 44109615.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (96).

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 15 ways as a sum of consecutive naturals, for example, 31947 + ... + 33525.

It is an arithmetic number, because the mean of its divisors is an integer number (1592640).

Almost surely, 2^51690144 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 51690144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76446720).

51690144 is an abundant number, since it is smaller than the sum of its proper divisors (101203296).

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

51690144 is a wasteful number, since it uses less digits than its factorization.

With its predecessor (51690143) it forms an eRAP, since the sums of their prime factors are consecutive (1633 and 1634).

51690144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1634 (or 1626 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 51690144 is about 7189.5858016996. The cubic root of 51690144 is about 372.5082658106.

Adding to 51690144 its reverse (44109615), we get a palindrome (95799759).

The spelling of 51690144 in words is "fifty-one million, six hundred ninety thousand, one hundred forty-four".