21213402433 has 2 divisors, whose sum is σ = 21213402434. Its totient is φ = 21213402432.

The previous prime is 21213402421. The next prime is 21213402503. The reversal of 21213402433 is 33420431212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19844920384 + 1368482049 = 140872^2 + 36993^2 .

It is a cyclic number.

It is not a de Polignac number, because 21213402433 - 2⁵ = 21213402401 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21213402398 and 21213402407.

It is not a weakly prime, because it can be changed into another prime (21213402533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606701216 + 10606701217.

It is an arithmetic number, because the mean of its divisors is an integer number (10606701217).

Almost surely, 2^21213402433 is an apocalyptic number.

It is an amenable number.

21213402433 is a deficient number, since it is larger than the sum of its proper divisors (1).

21213402433 is an equidigital number, since it uses as much as digits as its factorization.

21213402433 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 25.

Adding to 21213402433 its reverse (33420431212), we get a palindrome (54633833645).

The spelling of 21213402433 in words is "twenty-one billion, two hundred thirteen million, four hundred two thousand, four hundred thirty-three".