128720047 has 2 divisors, whose sum is σ = 128720048. Its totient is φ = 128720046.

The previous prime is 128720023. The next prime is 128720051. The reversal of 128720047 is 740027821.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 128720047 - 2⁷ = 128719919 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128720017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64360023 + 64360024.

It is an arithmetic number, because the mean of its divisors is an integer number (64360024).

Almost surely, 2^128720047 is an apocalyptic number.

128720047 is a deficient number, since it is larger than the sum of its proper divisors (1).

128720047 is an equidigital number, since it uses as much as digits as its factorization.

128720047 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6272, while the sum is 31.

The square root of 128720047 is about 11345.4857542549. The cubic root of 128720047 is about 504.9116559509.

Adding to 128720047 its reverse (740027821), we get a palindrome (868747868).

The spelling of 128720047 in words is "one hundred twenty-eight million, seven hundred twenty thousand, forty-seven".