55924721 has 4 divisors (see below), whose sum is σ = 55981812. Its totient is φ = 55867632.

The previous prime is 55924711. The next prime is 55924741. The reversal of 55924721 is 12742955.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12742955 = 5 ⋅2548591.

It can be written as a sum of positive squares in 2 ways, for example, as 30924721 + 25000000 = 5561^2 + 5000^2 .

It is a cyclic number.

It is not a de Polignac number, because 55924721 - 2¹⁰ = 55923697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55924711) 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, 27050 + ... + 29043.

It is an arithmetic number, because the mean of its divisors is an integer number (13995453).

Almost surely, 2^55924721 is an apocalyptic number.

It is an amenable number.

55924721 is a deficient number, since it is larger than the sum of its proper divisors (57091).

55924721 is an equidigital number, since it uses as much as digits as its factorization.

55924721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57090.

The product of its digits is 25200, while the sum is 35.

The square root of 55924721 is about 7478.2832923071. The cubic root of 55924721 is about 382.4147268864.

The spelling of 55924721 in words is "fifty-five million, nine hundred twenty-four thousand, seven hundred twenty-one".