21216211422433 has 16 divisors (see below), whose sum is σ = 21384605092032. Its totient is φ = 21048411384000.

The previous prime is 21216211422431. The next prime is 21216211422463. The reversal of 21216211422433 is 33422411261212.

It is a cyclic number.

It is not a de Polignac number, because 21216211422433 - 2¹ = 21216211422431 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21216211422431) 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, 254218210 + ... + 254301652.

It is an arithmetic number, because the mean of its divisors is an integer number (1336537818252).

Almost surely, 2^{21216211422433} is an apocalyptic number.

It is an amenable number.

21216211422433 is a deficient number, since it is larger than the sum of its proper divisors (168393669599).

21216211422433 is a wasteful number, since it uses less digits than its factorization.

21216211422433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86976.

The product of its digits is 27648, while the sum is 34.

Adding to 21216211422433 its reverse (33422411261212), we get a palindrome (54638622683645).

The spelling of 21216211422433 in words is "twenty-one trillion, two hundred sixteen billion, two hundred eleven million, four hundred twenty-two thousand, four hundred thirty-three".