20231421 has 16 divisors (see below), whose sum is σ = 32169984. Its totient is φ = 11057904.

The previous prime is 20231417. The next prime is 20231423. The reversal of 20231421 is 12413202.

It is not a de Polignac number, because 20231421 - 2² = 20231417 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20231421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20231423) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20461 + ... + 21426.

It is an arithmetic number, because the mean of its divisors is an integer number (2010624).

Almost surely, 2^20231421 is an apocalyptic number.

20231421 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20231421 is a deficient number, since it is larger than the sum of its proper divisors (11938563).

20231421 is a wasteful number, since it uses less digits than its factorization.

20231421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41920.

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 20231421 is about 4497.9351929524. The cubic root of 20231421 is about 272.4847046938.

Adding to 20231421 its reverse (12413202), we get a palindrome (32644623).

The spelling of 20231421 in words is "twenty million, two hundred thirty-one thousand, four hundred twenty-one".