20890151 has 4 divisors (see below), whose sum is σ = 21093072. Its totient is φ = 20687232.

The previous prime is 20890099. The next prime is 20890183. The reversal of 20890151 is 15109802.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20890151 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 20890151.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20890351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 101306 + ... + 101511.

It is an arithmetic number, because the mean of its divisors is an integer number (5273268).

Almost surely, 2^20890151 is an apocalyptic number.

20890151 is a deficient number, since it is larger than the sum of its proper divisors (202921).

20890151 is a wasteful number, since it uses less digits than its factorization.

20890151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 202920.

The product of its (nonzero) digits is 720, while the sum is 26.

The square root of 20890151 is about 4570.5744715517. The cubic root of 20890151 is about 275.4105207529.

Adding to 20890151 its reverse (15109802), we get a palindrome (35999953).

The spelling of 20890151 in words is "twenty million, eight hundred ninety thousand, one hundred fifty-one".