20881151 has 4 divisors (see below), whose sum is σ = 22109472. Its totient is φ = 19652832.

The previous prime is 20881141. The next prime is 20881163. The reversal of 20881151 is 15118802.

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 20881151 - 2²² = 16686847 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20881151.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20881111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 614135 + ... + 614168.

It is an arithmetic number, because the mean of its divisors is an integer number (5527368).

Almost surely, 2^20881151 is an apocalyptic number.

20881151 is a deficient number, since it is larger than the sum of its proper divisors (1228321).

20881151 is a wasteful number, since it uses less digits than its factorization.

20881151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1228320.

The product of its (nonzero) digits is 640, while the sum is 26.

The square root of 20881151 is about 4569.5898065362. The cubic root of 20881151 is about 275.3709638227.

Adding to 20881151 its reverse (15118802), we get a palindrome (35999953).

The spelling of 20881151 in words is "twenty million, eight hundred eighty-one thousand, one hundred fifty-one".