20533233491 has 2 divisors, whose sum is σ = 20533233492. Its totient is φ = 20533233490.

The previous prime is 20533233467. The next prime is 20533233517. The reversal of 20533233491 is 19433233502.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20533233491 is a prime.

It is a super-2 number, since 2×20533233491² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20533233401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10266616745 + 10266616746.

It is an arithmetic number, because the mean of its divisors is an integer number (10266616746).

Almost surely, 2^20533233491 is an apocalyptic number.

20533233491 is a deficient number, since it is larger than the sum of its proper divisors (1).

20533233491 is an equidigital number, since it uses as much as digits as its factorization.

20533233491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 58320, while the sum is 35.

Adding to 20533233491 its reverse (19433233502), we get a palindrome (39966466993).

The spelling of 20533233491 in words is "twenty billion, five hundred thirty-three million, two hundred thirty-three thousand, four hundred ninety-one".