21677263187 has 2 divisors, whose sum is σ = 21677263188. Its totient is φ = 21677263186.

The previous prime is 21677263183. The next prime is 21677263199. The reversal of 21677263187 is 78136277612.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21677263187 - 2² = 21677263183 is a prime.

It is not a weakly prime, because it can be changed into another prime (21677263183) 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, 10838631593 + 10838631594.

It is an arithmetic number, because the mean of its divisors is an integer number (10838631594).

Almost surely, 2^21677263187 is an apocalyptic number.

21677263187 is a deficient number, since it is larger than the sum of its proper divisors (1).

21677263187 is an equidigital number, since it uses as much as digits as its factorization.

21677263187 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1185408, while the sum is 50.

The spelling of 21677263187 in words is "twenty-one billion, six hundred seventy-seven million, two hundred sixty-three thousand, one hundred eighty-seven".