11138821 has 2 divisors, whose sum is σ = 11138822. Its totient is φ = 11138820.

The previous prime is 11138767. The next prime is 11138833. The reversal of 11138821 is 12883111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10824100 + 314721 = 3290^2 + 561^2 .

It is an emirp because it is prime and its reverse (12883111) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 11138821 - 2¹³ = 11130629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11138891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5569410 + 5569411.

It is an arithmetic number, because the mean of its divisors is an integer number (5569411).

Almost surely, 2^11138821 is an apocalyptic number.

It is an amenable number.

11138821 is a deficient number, since it is larger than the sum of its proper divisors (1).

11138821 is an equidigital number, since it uses as much as digits as its factorization.

11138821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 384, while the sum is 25.

The square root of 11138821 is about 3337.4872284400. The cubic root of 11138821 is about 223.3296618292.

The spelling of 11138821 in words is "eleven million, one hundred thirty-eight thousand, eight hundred twenty-one".