6403381 has 2 divisors, whose sum is σ = 6403382. Its totient is φ = 6403380.

The previous prime is 6403379. The next prime is 6403387. The reversal of 6403381 is 1833046.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5267025 + 1136356 = 2295^2 + 1066^2 .

It is a cyclic number.

It is not a de Polignac number, because 6403381 - 2¹ = 6403379 is a prime.

It is a super-2 number, since 2×6403381² = 82006576462322, which contains 22 as substring.

Together with 6403379, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6403387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3201690 + 3201691.

It is an arithmetic number, because the mean of its divisors is an integer number (3201691).

Almost surely, 2^6403381 is an apocalyptic number.

It is an amenable number.

6403381 is a deficient number, since it is larger than the sum of its proper divisors (1).

6403381 is an equidigital number, since it uses as much as digits as its factorization.

6403381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 6403381 is about 2530.4902687029. The cubic root of 6403381 is about 185.6962417803.

The spelling of 6403381 in words is "six million, four hundred three thousand, three hundred eighty-one".