1445731909 has 2 divisors, whose sum is σ = 1445731910. Its totient is φ = 1445731908.

The previous prime is 1445731897. The next prime is 1445731943. The reversal of 1445731909 is 9091375441.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1063412100 + 382319809 = 32610^2 + 19553^2 .

It is an emirp because it is prime and its reverse (9091375441) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1445731909 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1445731949) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 722865954 + 722865955.

It is an arithmetic number, because the mean of its divisors is an integer number (722865955).

Almost surely, 2^1445731909 is an apocalyptic number.

It is an amenable number.

1445731909 is a deficient number, since it is larger than the sum of its proper divisors (1).

1445731909 is an equidigital number, since it uses as much as digits as its factorization.

1445731909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 136080, while the sum is 43.

The square root of 1445731909 is about 38022.7814474428. The cubic root of 1445731909 is about 1130.7395657216.

The spelling of 1445731909 in words is "one billion, four hundred forty-five million, seven hundred thirty-one thousand, nine hundred nine".