51561655 has 8 divisors (see below), whose sum is σ = 62042112. Its totient is φ = 41137248.

The previous prime is 51561637. The next prime is 51561673. The reversal of 51561655 is 55616515.

51561655 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (51561637) and next prime (51561673).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51561655 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51561655.

It is a congruent number.

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, 11959 + ... + 15688.

It is an arithmetic number, because the mean of its divisors is an integer number (7755264).

Almost surely, 2^51561655 is an apocalyptic number.

51561655 is a deficient number, since it is larger than the sum of its proper divisors (10480457).

51561655 is a wasteful number, since it uses less digits than its factorization.

51561655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28025.

The product of its digits is 22500, while the sum is 34.

The square root of 51561655 is about 7180.6444696838. The cubic root of 51561655 is about 372.1993550303.

The spelling of 51561655 in words is "fifty-one million, five hundred sixty-one thousand, six hundred fifty-five".