21216531152303 has 4 divisors (see below), whose sum is σ = 21216812498448. Its totient is φ = 21216249806160.

The previous prime is 21216531152293. The next prime is 21216531152321. The reversal of 21216531152303 is 30325113561212.

It is a happy number.

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 21216531152303 - 2¹⁰ = 21216531151279 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21216531152353) 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, 140559926 + ... + 140710787.

It is an arithmetic number, because the mean of its divisors is an integer number (5304203124612).

Almost surely, 2^{21216531152303} is an apocalyptic number.

21216531152303 is a deficient number, since it is larger than the sum of its proper divisors (281346145).

21216531152303 is an equidigital number, since it uses as much as digits as its factorization.

21216531152303 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281346144.

The product of its (nonzero) digits is 32400, while the sum is 35.

The spelling of 21216531152303 in words is "twenty-one trillion, two hundred sixteen billion, five hundred thirty-one million, one hundred fifty-two thousand, three hundred three".