21414811987 has 2 divisors, whose sum is σ = 21414811988. Its totient is φ = 21414811986.

The previous prime is 21414811949. The next prime is 21414812051. The reversal of 21414811987 is 78911841412.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21414811987 is a prime.

It is not a weakly prime, because it can be changed into another prime (21414811387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10707405993 + 10707405994.

It is an arithmetic number, because the mean of its divisors is an integer number (10707405994).

Almost surely, 2^21414811987 is an apocalyptic number.

21414811987 is a deficient number, since it is larger than the sum of its proper divisors (1).

21414811987 is an equidigital number, since it uses as much as digits as its factorization.

21414811987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 129024, while the sum is 46.

The spelling of 21414811987 in words is "twenty-one billion, four hundred fourteen million, eight hundred eleven thousand, nine hundred eighty-seven".