55721271 has 4 divisors (see below), whose sum is σ = 74295032. Its totient is φ = 37147512.

The previous prime is 55721269. The next prime is 55721293. The reversal of 55721271 is 17212755.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 55721271 - 2¹ = 55721269 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55721201) 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, 9286876 + ... + 9286881.

It is an arithmetic number, because the mean of its divisors is an integer number (18573758).

Almost surely, 2^55721271 is an apocalyptic number.

55721271 is a deficient number, since it is larger than the sum of its proper divisors (18573761).

55721271 is a wasteful number, since it uses less digits than its factorization.

55721271 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18573760.

The product of its digits is 4900, while the sum is 30.

The square root of 55721271 is about 7464.6681774879. The cubic root of 55721271 is about 381.9504312389.

The spelling of 55721271 in words is "fifty-five million, seven hundred twenty-one thousand, two hundred seventy-one".