145440391 has 2 divisors, whose sum is σ = 145440392. Its totient is φ = 145440390.

The previous prime is 145440371. The next prime is 145440413. The reversal of 145440391 is 193044541.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 145440391 - 2⁵ = 145440359 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (145440301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72720195 + 72720196.

It is an arithmetic number, because the mean of its divisors is an integer number (72720196).

Almost surely, 2^145440391 is an apocalyptic number.

145440391 is a deficient number, since it is larger than the sum of its proper divisors (1).

145440391 is an equidigital number, since it uses as much as digits as its factorization.

145440391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 145440391 is about 12059.8669561484. The cubic root of 145440391 is about 525.8901193079.

The spelling of 145440391 in words is "one hundred forty-five million, four hundred forty thousand, three hundred ninety-one".