20012381 has 2 divisors, whose sum is σ = 20012382. Its totient is φ = 20012380.

The previous prime is 20012371. The next prime is 20012389. The reversal of 20012381 is 18321002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16736281 + 3276100 = 4091^2 + 1810^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20012381 is a prime.

It is a super-2 number, since 2×20012381² = 800990786578322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20012389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10006190 + 10006191.

It is an arithmetic number, because the mean of its divisors is an integer number (10006191).

Almost surely, 2^20012381 is an apocalyptic number.

It is an amenable number.

20012381 is a deficient number, since it is larger than the sum of its proper divisors (1).

20012381 is an equidigital number, since it uses as much as digits as its factorization.

20012381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 20012381 is about 4473.5199787192. The cubic root of 20012381 is about 271.4977621129.

Adding to 20012381 its reverse (18321002), we get a palindrome (38333383).

The spelling of 20012381 in words is "twenty million, twelve thousand, three hundred eighty-one".