55721263 has 4 divisors (see below), whose sum is σ = 60007528. Its totient is φ = 51435000.

The previous prime is 55721261. The next prime is 55721269. The reversal of 55721263 is 36212755.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 36212755 = 5 ⋅7242551.

It is a cyclic number.

It is not a de Polignac number, because 55721263 - 2¹ = 55721261 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 (55721261) 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, 2143113 + ... + 2143138.

It is an arithmetic number, because the mean of its divisors is an integer number (15001882).

Almost surely, 2^55721263 is an apocalyptic number.

55721263 is a deficient number, since it is larger than the sum of its proper divisors (4286265).

55721263 is a wasteful number, since it uses less digits than its factorization.

55721263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4286264.

The product of its digits is 12600, while the sum is 31.

The square root of 55721263 is about 7464.6676416301. The cubic root of 55721263 is about 381.9504129598.

The spelling of 55721263 in words is "fifty-five million, seven hundred twenty-one thousand, two hundred sixty-three".