51621544 has 32 divisors (see below), whose sum is σ = 105719040. Its totient is φ = 23486400.

The previous prime is 51621539. The next prime is 51621551. The reversal of 51621544 is 44512615.

51621544 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3889 + ... + 10879.

It is an arithmetic number, because the mean of its divisors is an integer number (3303720).

Almost surely, 2^51621544 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 51621544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52859520).

51621544 is an abundant number, since it is smaller than the sum of its proper divisors (54097496).

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

51621544 is a wasteful number, since it uses less digits than its factorization.

51621544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7081 (or 7077 counting only the distinct ones).

The product of its digits is 4800, while the sum is 28.

The square root of 51621544 is about 7184.8134283362. The cubic root of 51621544 is about 372.3434027890.

The spelling of 51621544 in words is "fifty-one million, six hundred twenty-one thousand, five hundred forty-four".