21495117 has 8 divisors (see below), whose sum is σ = 32754496. Its totient is φ = 12282912.

The previous prime is 21495107. The next prime is 21495143. The reversal of 21495117 is 71159412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21495117 - 2⁴ = 21495101 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 (21495107) 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, 511768 + ... + 511809.

It is an arithmetic number, because the mean of its divisors is an integer number (4094312).

Almost surely, 2^21495117 is an apocalyptic number.

It is an amenable number.

21495117 is a deficient number, since it is larger than the sum of its proper divisors (11259379).

21495117 is a wasteful number, since it uses less digits than its factorization.

21495117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1023587.

The product of its digits is 2520, while the sum is 30.

The square root of 21495117 is about 4636.2826704160. The cubic root of 21495117 is about 278.0438357113.

It can be divided in two parts, 21495 and 117, that added together give a palindrome (21612).

The spelling of 21495117 in words is "twenty-one million, four hundred ninety-five thousand, one hundred seventeen".