99778271 has 2 divisors, whose sum is σ = 99778272. Its totient is φ = 99778270.

The previous prime is 99778267. The next prime is 99778309. The reversal of 99778271 is 17287799.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 99778271 - 2² = 99778267 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99778571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49889135 + 49889136.

It is an arithmetic number, because the mean of its divisors is an integer number (49889136).

Almost surely, 2^99778271 is an apocalyptic number.

99778271 is a deficient number, since it is larger than the sum of its proper divisors (1).

99778271 is an equidigital number, since it uses as much as digits as its factorization.

99778271 is an evil number, because the sum of its binary digits is even.

The product of its digits is 444528, while the sum is 50.

The square root of 99778271 is about 9988.9073977087. The cubic root of 99778271 is about 463.8155712118.

The spelling of 99778271 in words is "ninety-nine million, seven hundred seventy-eight thousand, two hundred seventy-one".