145215391 has 2 divisors, whose sum is σ = 145215392. Its totient is φ = 145215390.

The previous prime is 145215349. The next prime is 145215401. The reversal of 145215391 is 193512541.

It is a strong prime.

It is an emirp because it is prime and its reverse (193512541) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 145215391 - 2¹⁷ = 145084319 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (145210391) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72607695 + 72607696.

It is an arithmetic number, because the mean of its divisors is an integer number (72607696).

Almost surely, 2^145215391 is an apocalyptic number.

145215391 is a deficient number, since it is larger than the sum of its proper divisors (1).

145215391 is an equidigital number, since it uses as much as digits as its factorization.

145215391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5400, while the sum is 31.

The square root of 145215391 is about 12050.5348843941. The cubic root of 145215391 is about 525.6187908598.

The spelling of 145215391 in words is "one hundred forty-five million, two hundred fifteen thousand, three hundred ninety-one".