21126151 has 4 divisors (see below), whose sum is σ = 21147304. Its totient is φ = 21105000.

The previous prime is 21126109. The next prime is 21126169. The reversal of 21126151 is 15162112.

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 21126151 - 2⁷ = 21126023 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 (21126451) 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, 9000 + ... + 11101.

It is an arithmetic number, because the mean of its divisors is an integer number (5286826).

Almost surely, 2^21126151 is an apocalyptic number.

21126151 is a deficient number, since it is larger than the sum of its proper divisors (21153).

21126151 is a wasteful number, since it uses less digits than its factorization.

21126151 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21152.

The product of its digits is 120, while the sum is 19.

The square root of 21126151 is about 4596.3192883002. The cubic root of 21126151 is about 276.4437612001.

Adding to 21126151 its reverse (15162112), we get a palindrome (36288263).

It can be divided in two parts, 211 and 26151, that added together give a palindrome (26362).

The spelling of 21126151 in words is "twenty-one million, one hundred twenty-six thousand, one hundred fifty-one".