21031424429 has 2 divisors, whose sum is σ = 21031424430. Its totient is φ = 21031424428.

The previous prime is 21031424377. The next prime is 21031424441. The reversal of 21031424429 is 92442413012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20815275625 + 216148804 = 144275^2 + 14702^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21031424429 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21031424395 and 21031424404.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21031424929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515712214 + 10515712215.

It is an arithmetic number, because the mean of its divisors is an integer number (10515712215).

Almost surely, 2^21031424429 is an apocalyptic number.

It is an amenable number.

21031424429 is a deficient number, since it is larger than the sum of its proper divisors (1).

21031424429 is an equidigital number, since it uses as much as digits as its factorization.

21031424429 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13824, while the sum is 32.

The spelling of 21031424429 in words is "twenty-one billion, thirty-one million, four hundred twenty-four thousand, four hundred twenty-nine".