21616205212563 has 16 divisors (see below), whose sum is σ = 31038754006176. Its totient is φ = 13302237116160.

The previous prime is 21616205212559. The next prime is 21616205212579. The reversal of 21616205212563 is 36521250261612.

It is not a de Polignac number, because 21616205212563 - 2² = 21616205212559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21616205212583) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14798673 + ... + 16193613.

It is an arithmetic number, because the mean of its divisors is an integer number (1939922125386).

Almost surely, 2^{21616205212563} is an apocalyptic number.

21616205212563 is a deficient number, since it is larger than the sum of its proper divisors (9422548793613).

21616205212563 is a wasteful number, since it uses less digits than its factorization.

21616205212563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1792294.

The product of its (nonzero) digits is 259200, while the sum is 42.

The spelling of 21616205212563 in words is "twenty-one trillion, six hundred sixteen billion, two hundred five million, two hundred twelve thousand, five hundred sixty-three".