56017821 has 8 divisors (see below), whose sum is σ = 77266080. Its totient is φ = 36057392.

The previous prime is 56017813. The next prime is 56017831. The reversal of 56017821 is 12871065.

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 56017821 - 2³ = 56017813 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56017831) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 321855 + ... + 322028.

It is an arithmetic number, because the mean of its divisors is an integer number (9658260).

Almost surely, 2^56017821 is an apocalyptic number.

It is an amenable number.

56017821 is a deficient number, since it is larger than the sum of its proper divisors (21248259).

56017821 is a wasteful number, since it uses less digits than its factorization.

56017821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 643915.

The product of its (nonzero) digits is 3360, while the sum is 30.

The square root of 56017821 is about 7484.5053944800. The cubic root of 56017821 is about 382.6268159962.

Adding to 56017821 its reverse (12871065), we get a palindrome (68888886).

It can be divided in two parts, 560 and 17821, that added together give a palindrome (18381).

The spelling of 56017821 in words is "fifty-six million, seventeen thousand, eight hundred twenty-one".