21116203026523 has 4 divisors (see below), whose sum is σ = 23035857847128. Its totient is φ = 19196548205920.

The previous prime is 21116203026497. The next prime is 21116203026587. The reversal of 21116203026523 is 32562030261112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21116203026523 - 2¹⁷ = 21116202895451 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21116203026323) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 959827410286 + ... + 959827410307.

It is an arithmetic number, because the mean of its divisors is an integer number (5758964461782).

Almost surely, 2^{21116203026523} is an apocalyptic number.

21116203026523 is a deficient number, since it is larger than the sum of its proper divisors (1919654820605).

21116203026523 is a wasteful number, since it uses less digits than its factorization.

21116203026523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1919654820604.

The product of its (nonzero) digits is 25920, while the sum is 34.

Adding to 21116203026523 its reverse (32562030261112), we get a palindrome (53678233287635).

The spelling of 21116203026523 in words is "twenty-one trillion, one hundred sixteen billion, two hundred three million, twenty-six thousand, five hundred twenty-three".