21044433431 has 8 divisors (see below), whose sum is σ = 24060825600. Its totient is φ = 18030552408.

The previous prime is 21044433413. The next prime is 21044433461. The reversal of 21044433431 is 13433444012.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21044433431 is a prime.

It is a super-2 number, since 2×21044433431² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21044433394 and 21044433403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21044433461) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 609791 + ... + 643376.

It is an arithmetic number, because the mean of its divisors is an integer number (3007603200).

Almost surely, 2^21044433431 is an apocalyptic number.

21044433431 is a deficient number, since it is larger than the sum of its proper divisors (3016392169).

21044433431 is a wasteful number, since it uses less digits than its factorization.

21044433431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1255573.

The product of its (nonzero) digits is 13824, while the sum is 29.

Adding to 21044433431 its reverse (13433444012), we get a palindrome (34477877443).

The spelling of 21044433431 in words is "twenty-one billion, forty-four million, four hundred thirty-three thousand, four hundred thirty-one".