21415017 has 16 divisors (see below), whose sum is σ = 31743488. Its totient is φ = 12752640.

The previous prime is 21414983. The next prime is 21415027. The reversal of 21415017 is 71051412.

It is a happy number.

It is not a de Polignac number, because 21415017 - 2⁸ = 21414761 is a prime.

It is a super-2 number, since 2×21415017² = 917205906220578, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21414984 and 21415002.

It is not an unprimeable number, because it can be changed into a prime (21415027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7648 + ... + 10065.

It is an arithmetic number, because the mean of its divisors is an integer number (1983968).

Almost surely, 2^21415017 is an apocalyptic number.

It is an amenable number.

21415017 is a deficient number, since it is larger than the sum of its proper divisors (10328471).

21415017 is a wasteful number, since it uses less digits than its factorization.

21415017 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17760.

The product of its (nonzero) digits is 280, while the sum is 21.

The square root of 21415017 is about 4627.6362216579. The cubic root of 21415017 is about 277.6980357357.

Adding to 21415017 its reverse (71051412), we get a palindrome (92466429).

The spelling of 21415017 in words is "twenty-one million, four hundred fifteen thousand, seventeen".