20415421 has 8 divisors (see below), whose sum is σ = 22942080. Its totient is φ = 18025392.

The previous prime is 20415401. The next prime is 20415431. The reversal of 20415421 is 12451402.

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 20415421 - 2⁵ = 20415389 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 (20415401) 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, 33841 + ... + 34438.

It is an arithmetic number, because the mean of its divisors is an integer number (2867760).

Almost surely, 2^20415421 is an apocalyptic number.

It is an amenable number.

20415421 is a deficient number, since it is larger than the sum of its proper divisors (2526659).

20415421 is a wasteful number, since it uses less digits than its factorization.

20415421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68315.

The product of its (nonzero) digits is 320, while the sum is 19.

The square root of 20415421 is about 4518.3427271512. The cubic root of 20415421 is about 273.3082743568.

Adding to 20415421 its reverse (12451402), we get a palindrome (32866823).

It can be divided in two parts, 204 and 15421, that added together give a 6-th power (15625 = 5⁶).

The spelling of 20415421 in words is "twenty million, four hundred fifteen thousand, four hundred twenty-one".