21201011387 has 2 divisors, whose sum is σ = 21201011388. Its totient is φ = 21201011386.

The previous prime is 21201011371. The next prime is 21201011401. The reversal of 21201011387 is 78311010212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21201011387 - 2⁴ = 21201011371 is a prime.

It is not a weakly prime, because it can be changed into another prime (21201011087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600505693 + 10600505694.

It is an arithmetic number, because the mean of its divisors is an integer number (10600505694).

Almost surely, 2^21201011387 is an apocalyptic number.

21201011387 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201011387 is an equidigital number, since it uses as much as digits as its factorization.

21201011387 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 672, while the sum is 26.

Adding to 21201011387 its reverse (78311010212), we get a palindrome (99512021599).

The spelling of 21201011387 in words is "twenty-one billion, two hundred one million, eleven thousand, three hundred eighty-seven".