11561839 has 2 divisors, whose sum is σ = 11561840. Its totient is φ = 11561838.

The previous prime is 11561833. The next prime is 11561843. The reversal of 11561839 is 93816511.

It is a strong prime.

It is an emirp because it is prime and its reverse (93816511) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11561839 is a prime.

It is a super-2 number, since 2×11561839² = 267352242123842, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11561833) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5780919 + 5780920.

It is an arithmetic number, because the mean of its divisors is an integer number (5780920).

Almost surely, 2^11561839 is an apocalyptic number.

11561839 is a deficient number, since it is larger than the sum of its proper divisors (1).

11561839 is an equidigital number, since it uses as much as digits as its factorization.

11561839 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6480, while the sum is 34.

The square root of 11561839 is about 3400.2704304217. The cubic root of 11561839 is about 226.1217333054.

The spelling of 11561839 in words is "eleven million, five hundred sixty-one thousand, eight hundred thirty-nine".