51901565 has 8 divisors (see below), whose sum is σ = 63965400. Its totient is φ = 40398912.

The previous prime is 51901537. The next prime is 51901573. The reversal of 51901565 is 56510915.

It can be written as a sum of positive squares in 4 ways, for example, as 19945156 + 31956409 = 4466^2 + 5653^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 51901565 - 2⁸ = 51901309 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 140090 + ... + 140459.

It is an arithmetic number, because the mean of its divisors is an integer number (7995675).

Almost surely, 2^51901565 is an apocalyptic number.

It is an amenable number.

51901565 is a deficient number, since it is larger than the sum of its proper divisors (12063835).

51901565 is a wasteful number, since it uses less digits than its factorization.

51901565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 280591.

The product of its (nonzero) digits is 6750, while the sum is 32.

The square root of 51901565 is about 7204.2740786286. The cubic root of 51901565 is about 373.0154478529.

The spelling of 51901565 in words is "fifty-one million, nine hundred one thousand, five hundred sixty-five".