21038447738887 has 2 divisors, whose sum is σ = 21038447738888. Its totient is φ = 21038447738886.

The previous prime is 21038447738813. The next prime is 21038447738989. The reversal of 21038447738887 is 78883774483012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21038447738887 - 2¹⁵ = 21038447706119 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21038447738687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10519223869443 + 10519223869444.

It is an arithmetic number, because the mean of its divisors is an integer number (10519223869444).

Almost surely, 2^{21038447738887} is an apocalyptic number.

21038447738887 is a deficient number, since it is larger than the sum of its proper divisors (1).

21038447738887 is an equidigital number, since it uses as much as digits as its factorization.

21038447738887 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 404619264, while the sum is 70.

The spelling of 21038447738887 in words is "twenty-one trillion, thirty-eight billion, four hundred forty-seven million, seven hundred thirty-eight thousand, eight hundred eighty-seven".