381553813 has 2 divisors, whose sum is σ = 381553814. Its totient is φ = 381553812.

The previous prime is 381553807. The next prime is 381553853. The reversal of 381553813 is 318355183.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 316235089 + 65318724 = 17783^2 + 8082^2 .

It is a cyclic number.

It is not a de Polignac number, because 381553813 - 2¹³ = 381545621 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (381553853) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 190776906 + 190776907.

It is an arithmetic number, because the mean of its divisors is an integer number (190776907).

Almost surely, 2^381553813 is an apocalyptic number.

It is an amenable number.

381553813 is a deficient number, since it is larger than the sum of its proper divisors (1).

381553813 is an equidigital number, since it uses as much as digits as its factorization.

381553813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 43200, while the sum is 37.

The square root of 381553813 is about 19533.4024941893. The cubic root of 381553813 is about 725.3015395693.

The spelling of 381553813 in words is "three hundred eighty-one million, five hundred fifty-three thousand, eight hundred thirteen".