21144031435 has 16 divisors (see below), whose sum is σ = 26982698400. Its totient is φ = 15850676736.

The previous prime is 21144031429. The next prime is 21144031439. The reversal of 21144031435 is 53413044112.

It is a cyclic number.

It is not a de Polignac number, because 21144031435 - 2²⁷ = 21009813707 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21144031439) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 523665 + ... + 562594.

It is an arithmetic number, because the mean of its divisors is an integer number (1686418650).

Almost surely, 2^21144031435 is an apocalyptic number.

21144031435 is a deficient number, since it is larger than the sum of its proper divisors (5838666965).

21144031435 is a wasteful number, since it uses less digits than its factorization.

21144031435 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1086510.

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

Adding to 21144031435 its reverse (53413044112), we get a palindrome (74557075547).

The spelling of 21144031435 in words is "twenty-one billion, one hundred forty-four million, thirty-one thousand, four hundred thirty-five".