20371381 has 2 divisors, whose sum is σ = 20371382. Its totient is φ = 20371380.

The previous prime is 20371367. The next prime is 20371447. The reversal of 20371381 is 18317302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13950225 + 6421156 = 3735^2 + 2534^2 .

It is a cyclic number.

It is not a de Polignac number, because 20371381 - 2²¹ = 18274229 is a prime.

It is a super-2 number, since 2×20371381² = 829986327694322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20371331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10185690 + 10185691.

It is an arithmetic number, because the mean of its divisors is an integer number (10185691).

Almost surely, 2^20371381 is an apocalyptic number.

It is an amenable number.

20371381 is a deficient number, since it is larger than the sum of its proper divisors (1).

20371381 is an equidigital number, since it uses as much as digits as its factorization.

20371381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 20371381 is about 4513.4666277707. The cubic root of 20371381 is about 273.1116066547. Note that the first 3 decimals are identical.

Adding to 20371381 its reverse (18317302), we get a palindrome (38688683).

The spelling of 20371381 in words is "twenty million, three hundred seventy-one thousand, three hundred eighty-one".