381820013 has 4 divisors (see below), whose sum is σ = 381964800. Its totient is φ = 381675228.

The previous prime is 381820009. The next prime is 381820027. The reversal of 381820013 is 310028183.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 381820013 - 2² = 381820009 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381820063) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 68363 + ... + 73736.

It is an arithmetic number, because the mean of its divisors is an integer number (95491200).

Almost surely, 2^381820013 is an apocalyptic number.

It is an amenable number.

381820013 is a deficient number, since it is larger than the sum of its proper divisors (144787).

381820013 is a wasteful number, since it uses less digits than its factorization.

381820013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144786.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 381820013 is about 19540.2152751703. The cubic root of 381820013 is about 725.4701749225.

Adding to 381820013 its reverse (310028183), we get a palindrome (691848196).

The spelling of 381820013 in words is "three hundred eighty-one million, eight hundred twenty thousand, thirteen".