2138900381 has 4 divisors (see below), whose sum is σ = 2139692064. Its totient is φ = 2138108700.

The previous prime is 2138900377. The next prime is 2138900389. The reversal of 2138900381 is 1830098312.

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 2138900381 - 2² = 2138900377 is a prime.

It is a super-2 number, since 2×2138900381² = 9149789679683890322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2138900389) 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, 391775 + ... + 397196.

It is an arithmetic number, because the mean of its divisors is an integer number (534923016).

Almost surely, 2^2138900381 is an apocalyptic number.

It is an amenable number.

2138900381 is a deficient number, since it is larger than the sum of its proper divisors (791683).

2138900381 is an equidigital number, since it uses as much as digits as its factorization.

2138900381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 791682.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 2138900381 is about 46248.2473289529. The cubic root of 2138900381 is about 1288.4379829756.

Adding to 2138900381 its reverse (1830098312), we get a palindrome (3968998693).

The spelling of 2138900381 in words is "two billion, one hundred thirty-eight million, nine hundred thousand, three hundred eighty-one".