2121920429 has 2 divisors, whose sum is σ = 2121920430. Its totient is φ = 2121920428.

The previous prime is 2121920417. The next prime is 2121920431. The reversal of 2121920429 is 9240291212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1880956900 + 240963529 = 43370^2 + 15523^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2121920429 is a prime.

Together with 2121920431, 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 = 2121920395 and 2121920404.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2121920029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060960214 + 1060960215.

It is an arithmetic number, because the mean of its divisors is an integer number (1060960215).

Almost surely, 2^2121920429 is an apocalyptic number.

It is an amenable number.

2121920429 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121920429 is an equidigital number, since it uses as much as digits as its factorization.

2121920429 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 32.

The square root of 2121920429 is about 46064.3075384836. The cubic root of 2121920429 is about 1285.0194406260.

The spelling of 2121920429 in words is "two billion, one hundred twenty-one million, nine hundred twenty thousand, four hundred twenty-nine".