21059850187 has 2 divisors, whose sum is σ = 21059850188. Its totient is φ = 21059850186.

The previous prime is 21059850179. The next prime is 21059850247. The reversal of 21059850187 is 78105895012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21059850187 - 2³ = 21059850179 is a prime.

It is not a weakly prime, because it can be changed into another prime (21059850887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10529925093 + 10529925094.

It is an arithmetic number, because the mean of its divisors is an integer number (10529925094).

Almost surely, 2^21059850187 is an apocalyptic number.

21059850187 is a deficient number, since it is larger than the sum of its proper divisors (1).

21059850187 is an equidigital number, since it uses as much as digits as its factorization.

21059850187 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 201600, while the sum is 46.

The spelling of 21059850187 in words is "twenty-one billion, fifty-nine million, eight hundred fifty thousand, one hundred eighty-seven".