21231151 has 8 divisors (see below), whose sum is σ = 22619520. Its totient is φ = 19869912.

The previous prime is 21231143. The next prime is 21231173. The reversal of 21231151 is 15113212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21231151 - 2³ = 21231143 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21231851) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5155 + ... + 8308.

It is an arithmetic number, because the mean of its divisors is an integer number (2827440).

Almost surely, 2^21231151 is an apocalyptic number.

21231151 is a deficient number, since it is larger than the sum of its proper divisors (1388369).

21231151 is a wasteful number, since it uses less digits than its factorization.

21231151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13565.

The product of its digits is 60, while the sum is 16.

The square root of 21231151 is about 4607.7273139803. The cubic root of 21231151 is about 276.9009929109.

Adding to 21231151 its reverse (15113212), we get a palindrome (36344363).

The spelling of 21231151 in words is "twenty-one million, two hundred thirty-one thousand, one hundred fifty-one".