20671153 has 4 divisors (see below), whose sum is σ = 20962368. Its totient is φ = 20379940.

The previous prime is 20671151. The next prime is 20671159. The reversal of 20671153 is 35117602.

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 a cyclic number.

It is not a de Polignac number, because 20671153 - 2¹ = 20671151 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20671151) 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, 145501 + ... + 145642.

It is an arithmetic number, because the mean of its divisors is an integer number (5240592).

Almost surely, 2^20671153 is an apocalyptic number.

It is an amenable number.

20671153 is a deficient number, since it is larger than the sum of its proper divisors (291215).

20671153 is an equidigital number, since it uses as much as digits as its factorization.

20671153 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 291214.

The product of its (nonzero) digits is 1260, while the sum is 25.

The square root of 20671153 is about 4546.5539697666. The cubic root of 20671153 is about 274.4447330294. Note that the first 3 decimals are identical.

Adding to 20671153 its reverse (35117602), we get a palindrome (55788755).

The spelling of 20671153 in words is "twenty million, six hundred seventy-one thousand, one hundred fifty-three".