21132151 has 4 divisors (see below), whose sum is σ = 21175000. Its totient is φ = 21089304.

The previous prime is 21132131. The next prime is 21132191. The reversal of 21132151 is 15123112.

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 21132151 - 2⁵ = 21132119 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 (21132131) 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, 20676 + ... + 21673.

It is an arithmetic number, because the mean of its divisors is an integer number (5293750).

Almost surely, 2^21132151 is an apocalyptic number.

21132151 is a deficient number, since it is larger than the sum of its proper divisors (42849).

21132151 is an equidigital number, since it uses as much as digits as its factorization.

21132151 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42848.

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

The square root of 21132151 is about 4596.9719381349. The cubic root of 21132151 is about 276.4699294874.

Adding to 21132151 its reverse (15123112), we get a palindrome (36255263).

The spelling of 21132151 in words is "twenty-one million, one hundred thirty-two thousand, one hundred fifty-one".