20129951 has 2 divisors, whose sum is σ = 20129952. Its totient is φ = 20129950.

The previous prime is 20129929. The next prime is 20129953. The reversal of 20129951 is 15992102.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20129951 is a prime.

It is a Sophie Germain prime.

Together with 20129953, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20129953) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10064975 + 10064976.

It is an arithmetic number, because the mean of its divisors is an integer number (10064976).

Almost surely, 2^20129951 is an apocalyptic number.

20129951 is a deficient number, since it is larger than the sum of its proper divisors (1).

20129951 is an equidigital number, since it uses as much as digits as its factorization.

20129951 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1620, while the sum is 29.

The square root of 20129951 is about 4486.6413941834. The cubic root of 20129951 is about 272.0283950676.

The spelling of 20129951 in words is "twenty million, one hundred twenty-nine thousand, nine hundred fifty-one".