20550291 has 4 divisors (see below), whose sum is σ = 27400392. Its totient is φ = 13700192.

The previous prime is 20550289. The next prime is 20550301. The reversal of 20550291 is 19205502.

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

It is a cyclic number.

It is not a de Polignac number, because 20550291 - 2¹ = 20550289 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20550391) 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, 3425046 + ... + 3425051.

It is an arithmetic number, because the mean of its divisors is an integer number (6850098).

Almost surely, 2^20550291 is an apocalyptic number.

20550291 is a deficient number, since it is larger than the sum of its proper divisors (6850101).

20550291 is an equidigital number, since it uses as much as digits as its factorization.

20550291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6850100.

The product of its (nonzero) digits is 900, while the sum is 24.

The square root of 20550291 is about 4533.2428789995. The cubic root of 20550291 is about 273.9088042537.

Adding to 20550291 its reverse (19205502), we get a palindrome (39755793).

The spelling of 20550291 in words is "twenty million, five hundred fifty thousand, two hundred ninety-one".