51661544 has 16 divisors (see below), whose sum is σ = 105671520. Its totient is φ = 23482480.

The previous prime is 51661537. The next prime is 51661609. The reversal of 51661544 is 44516615.

It is a self number, because there is not a number n which added to its sum of digits gives 51661544.

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 3 ways as a sum of consecutive naturals, for example, 293444 + ... + 293619.

It is an arithmetic number, because the mean of its divisors is an integer number (6604470).

Almost surely, 2^51661544 is an apocalyptic number.

It is an amenable number.

51661544 is an abundant number, since it is smaller than the sum of its proper divisors (54009976).

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

51661544 is a wasteful number, since it uses less digits than its factorization.

51661544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 587080 (or 587076 counting only the distinct ones).

The product of its digits is 14400, while the sum is 32.

The square root of 51661544 is about 7187.5965384821. The cubic root of 51661544 is about 372.4395505709.

Subtracting from 51661544 its reverse (44516615), we obtain a square (7144929 = 2673²).

The spelling of 51661544 in words is "fifty-one million, six hundred sixty-one thousand, five hundred forty-four".