21330151 has 4 divisors (see below), whose sum is σ = 21784032. Its totient is φ = 20876272.

The previous prime is 21330149. The next prime is 21330157. The reversal of 21330151 is 15103312.

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

It is not a de Polignac number, because 21330151 - 2¹ = 21330149 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 (21330157) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 226870 + ... + 226963.

It is an arithmetic number, because the mean of its divisors is an integer number (5446008).

Almost surely, 2^21330151 is an apocalyptic number.

21330151 is a deficient number, since it is larger than the sum of its proper divisors (453881).

21330151 is an equidigital number, since it uses as much as digits as its factorization.

21330151 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 453880.

The product of its (nonzero) digits is 90, while the sum is 16.

The square root of 21330151 is about 4618.4576429800. The cubic root of 21330151 is about 277.3307183876.

Adding to 21330151 its reverse (15103312), we get a palindrome (36433463).

The spelling of 21330151 in words is "twenty-one million, three hundred thirty thousand, one hundred fifty-one".