21417151 has 8 divisors (see below), whose sum is σ = 24719904. Its totient is φ = 18175200.

The previous prime is 21417131. The next prime is 21417169. The reversal of 21417151 is 15171412.

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 21417151 - 2⁷ = 21417023 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 (21417131) 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, 14440 + ... + 15853.

It is an arithmetic number, because the mean of its divisors is an integer number (3089988).

Almost surely, 2^21417151 is an apocalyptic number.

21417151 is a deficient number, since it is larger than the sum of its proper divisors (3302753).

21417151 is a wasteful number, since it uses less digits than its factorization.

21417151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30401.

The product of its digits is 280, while the sum is 22.

The square root of 21417151 is about 4627.8667871926. The cubic root of 21417151 is about 277.7072596046.

Adding to 21417151 its reverse (15171412), we get a palindrome (36588563).

The spelling of 21417151 in words is "twenty-one million, four hundred seventeen thousand, one hundred fifty-one".