21204040033 has 12 divisors (see below), whose sum is σ = 24413218128. Its totient is φ = 18261849240.

The previous prime is 21204039991. The next prime is 21204040051. The reversal of 21204040033 is 33004040212.

It is not a de Polignac number, because 21204040033 - 2¹⁷ = 21203908961 is a prime.

It is a super-2 number, since 2×21204040033² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21204040063) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2665891 + ... + 2673832.

It is an arithmetic number, because the mean of its divisors is an integer number (2034434844).

Almost surely, 2^21204040033 is an apocalyptic number.

It is an amenable number.

21204040033 is a deficient number, since it is larger than the sum of its proper divisors (3209178095).

21204040033 is a wasteful number, since it uses less digits than its factorization.

21204040033 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5339772 (or 5339753 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 19.

Adding to 21204040033 its reverse (33004040212), we get a palindrome (54208080245).

The spelling of 21204040033 in words is "twenty-one billion, two hundred four million, forty thousand, thirty-three".