20424381 has 16 divisors (see below), whose sum is σ = 29084160. Its totient is φ = 12720960.

The previous prime is 20424379. The next prime is 20424401. The reversal of 20424381 is 18342402.

It is not a de Polignac number, because 20424381 - 2¹ = 20424379 is a prime.

It is a super-2 number, since 2×20424381² = 834310678466322, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20424301) 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, 1090 + ... + 6483.

It is an arithmetic number, because the mean of its divisors is an integer number (1817760).

Almost surely, 2^20424381 is an apocalyptic number.

It is an amenable number.

20424381 is a deficient number, since it is larger than the sum of its proper divisors (8659779).

20424381 is a wasteful number, since it uses less digits than its factorization.

20424381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7636.

The product of its (nonzero) digits is 1536, while the sum is 24.

The square root of 20424381 is about 4519.3341323695. The cubic root of 20424381 is about 273.3482520445.

Adding to 20424381 its reverse (18342402), we get a palindrome (38766783).

The spelling of 20424381 in words is "twenty million, four hundred twenty-four thousand, three hundred eighty-one".