20661267 has 16 divisors (see below), whose sum is σ = 30355200. Its totient is φ = 12396000.

The previous prime is 20661257. The next prime is 20661287. The reversal of 20661267 is 76216602.

It is not a de Polignac number, because 20661267 - 2⁶ = 20661203 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20661257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 234 + ... + 6432.

It is an arithmetic number, because the mean of its divisors is an integer number (1897200).

Almost surely, 2^20661267 is an apocalyptic number.

20661267 is a deficient number, since it is larger than the sum of its proper divisors (9693933).

20661267 is a wasteful number, since it uses less digits than its factorization.

20661267 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6314.

The product of its (nonzero) digits is 6048, while the sum is 30.

The square root of 20661267 is about 4545.4666427112. The cubic root of 20661267 is about 274.4009748950.

Adding to 20661267 its reverse (76216602), we get a palindrome (96877869).

It can be divided in two parts, 2066 and 1267, that added together give a palindrome (3333).

The spelling of 20661267 in words is "twenty million, six hundred sixty-one thousand, two hundred sixty-seven".