55010721 has 4 divisors (see below), whose sum is σ = 73347632. Its totient is φ = 36673812.

The previous prime is 55010701. The next prime is 55010723. The reversal of 55010721 is 12701055.

55010721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 not a de Polignac number, because 55010721 - 2¹⁵ = 54977953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55010723) 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, 9168451 + ... + 9168456.

It is an arithmetic number, because the mean of its divisors is an integer number (18336908).

Almost surely, 2^55010721 is an apocalyptic number.

It is an amenable number.

55010721 is a deficient number, since it is larger than the sum of its proper divisors (18336911).

55010721 is a wasteful number, since it uses less digits than its factorization.

55010721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18336910.

The product of its (nonzero) digits is 350, while the sum is 21.

The square root of 55010721 is about 7416.9212615478. The cubic root of 55010721 is about 380.3199544425.

Adding to 55010721 its reverse (12701055), we get a palindrome (67711776).

The spelling of 55010721 in words is "fifty-five million, ten thousand, seven hundred twenty-one".