127787993 has 2 divisors, whose sum is σ = 127787994. Its totient is φ = 127787992.

The previous prime is 127787981. The next prime is 127787999. The reversal of 127787993 is 399787721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 126270169 + 1517824 = 11237^2 + 1232^2 .

It is a cyclic number.

It is not a de Polignac number, because 127787993 - 2¹² = 127783897 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (127787999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63893996 + 63893997.

It is an arithmetic number, because the mean of its divisors is an integer number (63893997).

Almost surely, 2^127787993 is an apocalyptic number.

It is an amenable number.

127787993 is a deficient number, since it is larger than the sum of its proper divisors (1).

127787993 is an equidigital number, since it uses as much as digits as its factorization.

127787993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1333584, while the sum is 53.

The square root of 127787993 is about 11304.3351418825. The cubic root of 127787993 is about 503.6900244466.

The spelling of 127787993 in words is "one hundred twenty-seven million, seven hundred eighty-seven thousand, nine hundred ninety-three".