21421123033 has 2 divisors, whose sum is σ = 21421123034. Its totient is φ = 21421123032.

The previous prime is 21421123019. The next prime is 21421123063. The reversal of 21421123033 is 33032112412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21375317209 + 45805824 = 146203^2 + 6768^2 .

It is a cyclic number.

It is not a de Polignac number, because 21421123033 - 2⁵ = 21421123001 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21421122995 and 21421123013.

It is not a weakly prime, because it can be changed into another prime (21421123063) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10710561516 + 10710561517.

It is an arithmetic number, because the mean of its divisors is an integer number (10710561517).

Almost surely, 2^21421123033 is an apocalyptic number.

It is an amenable number.

21421123033 is a deficient number, since it is larger than the sum of its proper divisors (1).

21421123033 is an equidigital number, since it uses as much as digits as its factorization.

21421123033 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 22.

Adding to 21421123033 its reverse (33032112412), we get a palindrome (54453235445).

The spelling of 21421123033 in words is "twenty-one billion, four hundred twenty-one million, one hundred twenty-three thousand, thirty-three".