20415121 has 8 divisors (see below), whose sum is σ = 20865600. Its totient is φ = 19968240.

The previous prime is 20415119. The next prime is 20415133. The reversal of 20415121 is 12151402.

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 20415121 - 2¹ = 20415119 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20415095 and 20415104.

It is not an unprimeable number, because it can be changed into a prime (20415221) 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 7 ways as a sum of consecutive naturals, for example, 12756 + ... + 14266.

It is an arithmetic number, because the mean of its divisors is an integer number (2608200).

Almost surely, 2^20415121 is an apocalyptic number.

It is an amenable number.

20415121 is a deficient number, since it is larger than the sum of its proper divisors (450479).

20415121 is a wasteful number, since it uses less digits than its factorization.

20415121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1799.

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 20415121 is about 4518.3095290164. The cubic root of 20415121 is about 273.3069356158.

Adding to 20415121 its reverse (12151402), we get a palindrome (32566523).

The spelling of 20415121 in words is "twenty million, four hundred fifteen thousand, one hundred twenty-one".