145017991 has 2 divisors, whose sum is σ = 145017992. Its totient is φ = 145017990.

The previous prime is 145017953. The next prime is 145018001. The reversal of 145017991 is 199710541.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 145017991 - 2⁷ = 145017863 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 145017991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (145017941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72508995 + 72508996.

It is an arithmetic number, because the mean of its divisors is an integer number (72508996).

Almost surely, 2^145017991 is an apocalyptic number.

145017991 is a deficient number, since it is larger than the sum of its proper divisors (1).

145017991 is an equidigital number, since it uses as much as digits as its factorization.

145017991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11340, while the sum is 37.

The square root of 145017991 is about 12042.3415912355. The cubic root of 145017991 is about 525.3805144655.

The spelling of 145017991 in words is "one hundred forty-five million, seventeen thousand, nine hundred ninety-one".