56471721 has 4 divisors (see below), whose sum is σ = 75295632. Its totient is φ = 37647812.

The previous prime is 56471717. The next prime is 56471741. The reversal of 56471721 is 12717465.

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 56471721 - 2² = 56471717 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (56471741) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9411951 + ... + 9411956.

It is an arithmetic number, because the mean of its divisors is an integer number (18823908).

Almost surely, 2^56471721 is an apocalyptic number.

It is an amenable number.

56471721 is a deficient number, since it is larger than the sum of its proper divisors (18823911).

56471721 is a wasteful number, since it uses less digits than its factorization.

56471721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18823910.

The product of its digits is 11760, while the sum is 33.

The square root of 56471721 is about 7514.7668626512. The cubic root of 56471721 is about 383.6574840196.

The spelling of 56471721 in words is "fifty-six million, four hundred seventy-one thousand, seven hundred twenty-one".