145869491 has 2 divisors, whose sum is σ = 145869492. Its totient is φ = 145869490.

The previous prime is 145869467. The next prime is 145869509. The reversal of 145869491 is 194968541.

145869491 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is an emirp because it is prime and its reverse (194968541) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-145869491 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (145829491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72934745 + 72934746.

It is an arithmetic number, because the mean of its divisors is an integer number (72934746).

Almost surely, 2^145869491 is an apocalyptic number.

145869491 is a deficient number, since it is larger than the sum of its proper divisors (1).

145869491 is an equidigital number, since it uses as much as digits as its factorization.

145869491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 311040, while the sum is 47.

The square root of 145869491 is about 12077.6442653359. The cubic root of 145869491 is about 526.4067980813.

The spelling of 145869491 in words is "one hundred forty-five million, eight hundred sixty-nine thousand, four hundred ninety-one".