21433440187 has 2 divisors, whose sum is σ = 21433440188. Its totient is φ = 21433440186.

The previous prime is 21433440167. The next prime is 21433440191. The reversal of 21433440187 is 78104433412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21433440187 - 2²⁷ = 21299222459 is a prime.

It is not a weakly prime, because it can be changed into another prime (21433440167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10716720093 + 10716720094.

It is an arithmetic number, because the mean of its divisors is an integer number (10716720094).

Almost surely, 2^21433440187 is an apocalyptic number.

21433440187 is a deficient number, since it is larger than the sum of its proper divisors (1).

21433440187 is an equidigital number, since it uses as much as digits as its factorization.

21433440187 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 64512, while the sum is 37.

Adding to 21433440187 its reverse (78104433412), we get a palindrome (99537873599).

The spelling of 21433440187 in words is "twenty-one billion, four hundred thirty-three million, four hundred forty thousand, one hundred eighty-seven".