21040031429 has 2 divisors, whose sum is σ = 21040031430. Its totient is φ = 21040031428.

The previous prime is 21040031393. The next prime is 21040031431. The reversal of 21040031429 is 92413004012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17707624900 + 3332406529 = 133070^2 + 57727^2 .

It is a cyclic number.

It is not a de Polignac number, because 21040031429 - 2¹⁶ = 21039965893 is a prime.

Together with 21040031431, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21040031398 and 21040031407.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21040031029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10520015714 + 10520015715.

It is an arithmetic number, because the mean of its divisors is an integer number (10520015715).

Almost surely, 2^21040031429 is an apocalyptic number.

It is an amenable number.

21040031429 is a deficient number, since it is larger than the sum of its proper divisors (1).

21040031429 is an equidigital number, since it uses as much as digits as its factorization.

21040031429 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 26.

The spelling of 21040031429 in words is "twenty-one billion, forty million, thirty-one thousand, four hundred twenty-nine".