21492111187 has 2 divisors, whose sum is σ = 21492111188. Its totient is φ = 21492111186.

The previous prime is 21492111169. The next prime is 21492111197. The reversal of 21492111187 is 78111129412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21492111187 - 2¹⁹ = 21491586899 is a prime.

It is not a weakly prime, because it can be changed into another prime (21492111197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10746055593 + 10746055594.

It is an arithmetic number, because the mean of its divisors is an integer number (10746055594).

Almost surely, 2^21492111187 is an apocalyptic number.

21492111187 is a deficient number, since it is larger than the sum of its proper divisors (1).

21492111187 is an equidigital number, since it uses as much as digits as its factorization.

21492111187 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8064, while the sum is 37.

The spelling of 21492111187 in words is "twenty-one billion, four hundred ninety-two million, one hundred eleven thousand, one hundred eighty-seven".