21004235021143 has 32 divisors (see below), whose sum is σ = 23371080206400. Its totient is φ = 18873411335680.

The previous prime is 21004235021123. The next prime is 21004235021153. The reversal of 21004235021143 is 34112053240012.

It is not a de Polignac number, because 21004235021143 - 2¹⁷ = 21004234890071 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21004235021123) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 344566755 + ... + 344627707.

It is an arithmetic number, because the mean of its divisors is an integer number (730346256450).

Almost surely, 2^{21004235021143} is an apocalyptic number.

21004235021143 is a deficient number, since it is larger than the sum of its proper divisors (2366845185257).

21004235021143 is an equidigital number, since it uses as much as digits as its factorization.

21004235021143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63984 (or 63962 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 28.

Adding to 21004235021143 its reverse (34112053240012), we get a palindrome (55116288261155).

The spelling of 21004235021143 in words is "twenty-one trillion, four billion, two hundred thirty-five million, twenty-one thousand, one hundred forty-three".