20671245 has 48 divisors (see below), whose sum is σ = 41333760. Its totient is φ = 9361152.

The previous prime is 20671241. The next prime is 20671247. The reversal of 20671245 is 54217602.

It is not a de Polignac number, because 20671245 - 2² = 20671241 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20671241) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 42916 + ... + 43394.

It is an arithmetic number, because the mean of its divisors is an integer number (861120).

Almost surely, 2^20671245 is an apocalyptic number.

It is an amenable number.

20671245 is a deficient number, since it is larger than the sum of its proper divisors (20662515).

20671245 is a wasteful number, since it uses less digits than its factorization.

20671245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 634 (or 631 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 20671245 is about 4546.5640873081. The cubic root of 20671245 is about 274.4451401810.

Adding to 20671245 its reverse (54217602), we get a palindrome (74888847).

The spelling of 20671245 in words is "twenty million, six hundred seventy-one thousand, two hundred forty-five".