69856561 has 4 divisors (see below), whose sum is σ = 69890800. Its totient is φ = 69822324.

The previous prime is 69856541. The next prime is 69856571. The reversal of 69856561 is 16565896.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 69856561 - 2²³ = 61467953 is a prime.

It is a super-3 number, since 3×69856561³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (69856511) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 13851 + ... + 18208.

It is an arithmetic number, because the mean of its divisors is an integer number (17472700).

Almost surely, 2^69856561 is an apocalyptic number.

It is an amenable number.

69856561 is a deficient number, since it is larger than the sum of its proper divisors (34239).

69856561 is a wasteful number, since it uses less digits than its factorization.

69856561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34238.

The product of its digits is 388800, while the sum is 46.

The square root of 69856561 is about 8358.0237496671. The cubic root of 69856561 is about 411.8468360355.

The spelling of 69856561 in words is "sixty-nine million, eight hundred fifty-six thousand, five hundred sixty-one".