21121017 has 8 divisors (see below), whose sum is σ = 28547424. Its totient is φ = 13887648.

The previous prime is 21121003. The next prime is 21121033. The reversal of 21121017 is 71012112.

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

It is not a de Polignac number, because 21121017 - 2¹¹ = 21118969 is a prime.

It is a super-2 number, since 2×21121017² = 892194718228578, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21120987 and 21121005.

It is not an unprimeable number, because it can be changed into a prime (21121417) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48003 + ... + 48440.

It is an arithmetic number, because the mean of its divisors is an integer number (3568428).

Almost surely, 2^21121017 is an apocalyptic number.

It is an amenable number.

21121017 is a deficient number, since it is larger than the sum of its proper divisors (7426407).

21121017 is an equidigital number, since it uses as much as digits as its factorization.

21121017 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96519.

The product of its (nonzero) digits is 28, while the sum is 15.

The square root of 21121017 is about 4595.7607640085. The cubic root of 21121017 is about 276.4213659351.

Adding to 21121017 its reverse (71012112), we get a palindrome (92133129).

The spelling of 21121017 in words is "twenty-one million, one hundred twenty-one thousand, seventeen".