12433436821 has 16 divisors (see below), whose sum is σ = 13831325424. Its totient is φ = 11102206464.

The previous prime is 12433436819. The next prime is 12433436831. The reversal of 12433436821 is 12863433421.

It can be written as a sum of positive squares in 8 ways, for example, as 2521044100 + 9912392721 = 50210^2 + 99561^2 .

It is a cyclic number.

It is not a de Polignac number, because 12433436821 - 2¹ = 12433436819 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12433436831) 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, 8505 + ... + 157921.

It is an arithmetic number, because the mean of its divisors is an integer number (864457839).

Almost surely, 2^12433436821 is an apocalyptic number.

It is an amenable number.

12433436821 is a deficient number, since it is larger than the sum of its proper divisors (1397888603).

12433436821 is a wasteful number, since it uses less digits than its factorization.

12433436821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149640.

The product of its digits is 82944, while the sum is 37.

The spelling of 12433436821 in words is "twelve billion, four hundred thirty-three million, four hundred thirty-six thousand, eight hundred twenty-one".