148393991 has 2 divisors, whose sum is σ = 148393992. Its totient is φ = 148393990.

The previous prime is 148393981. The next prime is 148394021. The reversal of 148393991 is 199393841.

It is a weak prime.

It is an emirp because it is prime and its reverse (199393841) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-148393991 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (148393951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 74196995 + 74196996.

It is an arithmetic number, because the mean of its divisors is an integer number (74196996).

Almost surely, 2^148393991 is an apocalyptic number.

148393991 is a deficient number, since it is larger than the sum of its proper divisors (1).

148393991 is an equidigital number, since it uses as much as digits as its factorization.

148393991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 209952, while the sum is 47.

The square root of 148393991 is about 12181.7072284635. The cubic root of 148393991 is about 529.4262106402.

The spelling of 148393991 in words is "one hundred forty-eight million, three hundred ninety-three thousand, nine hundred ninety-one".