21452151 has 12 divisors (see below), whose sum is σ = 33272952. Its totient is φ = 12258288.

The previous prime is 21452149. The next prime is 21452161. The reversal of 21452151 is 15125412.

It is not a de Polignac number, because 21452151 - 2¹ = 21452149 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a plaindrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21452111) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 72820 + ... + 73113.

It is an arithmetic number, because the mean of its divisors is an integer number (2772746).

Almost surely, 2^21452151 is an apocalyptic number.

21452151 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21452151 is a deficient number, since it is larger than the sum of its proper divisors (11820801).

21452151 is a wasteful number, since it uses less digits than its factorization.

21452151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145950 (or 145943 counting only the distinct ones).

The product of its digits is 400, while the sum is 21.

The square root of 21452151 is about 4631.6466834162. The cubic root of 21452151 is about 277.8584540717.

Adding to 21452151 its reverse (15125412), we get a palindrome (36577563).

The spelling of 21452151 in words is "twenty-one million, four hundred fifty-two thousand, one hundred fifty-one".