21531512500103 has 2 divisors, whose sum is σ = 21531512500104. Its totient is φ = 21531512500102.

The previous prime is 21531512500063. The next prime is 21531512500279. The reversal of 21531512500103 is 30100521513512.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21531512500103 - 2¹² = 21531512496007 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21531518500103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10765756250051 + 10765756250052.

It is an arithmetic number, because the mean of its divisors is an integer number (10765756250052).

Almost surely, 2^{21531512500103} is an apocalyptic number.

21531512500103 is a deficient number, since it is larger than the sum of its proper divisors (1).

21531512500103 is an equidigital number, since it uses as much as digits as its factorization.

21531512500103 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4500, while the sum is 29.

The spelling of 21531512500103 in words is "twenty-one trillion, five hundred thirty-one billion, five hundred twelve million, five hundred thousand, one hundred three".