47920121 has 2 divisors, whose sum is σ = 47920122. Its totient is φ = 47920120.

The previous prime is 47920099. The next prime is 47920123. The reversal of 47920121 is 12102974.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 41473600 + 6446521 = 6440^2 + 2539^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-47920121 is a prime.

It is a Sophie Germain prime.

Together with 47920123, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (47920123) 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, 23960060 + 23960061.

It is an arithmetic number, because the mean of its divisors is an integer number (23960061).

Almost surely, 2^47920121 is an apocalyptic number.

It is an amenable number.

47920121 is a deficient number, since it is larger than the sum of its proper divisors (1).

47920121 is an equidigital number, since it uses as much as digits as its factorization.

47920121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1008, while the sum is 26.

The square root of 47920121 is about 6922.4360596541. The cubic root of 47920121 is about 363.2224097232. Note that the first 3 decimals are identical.

The spelling of 47920121 in words is "forty-seven million, nine hundred twenty thousand, one hundred twenty-one".