51861569 has 8 divisors (see below), whose sum is σ = 53196000. Its totient is φ = 50533056.

The previous prime is 51861559. The next prime is 51861571. The reversal of 51861569 is 96516815.

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 51861569 - 2⁴ = 51861553 is a prime.

It is a super-2 number, since 2×51861569² = 5379244678283522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51861559) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 20249 + ... + 22665.

It is an arithmetic number, because the mean of its divisors is an integer number (6649500).

Almost surely, 2^51861569 is an apocalyptic number.

It is an amenable number.

51861569 is a deficient number, since it is larger than the sum of its proper divisors (1334431).

51861569 is a wasteful number, since it uses less digits than its factorization.

51861569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2959.

The product of its digits is 64800, while the sum is 41.

The square root of 51861569 is about 7201.4976914528. The cubic root of 51861569 is about 372.9196064283.

The spelling of 51861569 in words is "fifty-one million, eight hundred sixty-one thousand, five hundred sixty-nine".