1445731906 has 4 divisors (see below), whose sum is σ = 2168597862. Its totient is φ = 722865952.

The previous prime is 1445731897. The next prime is 1445731909. The reversal of 1445731906 is 6091375441.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6091375441 = 29 ⋅210047429.

It can be written as a sum of positive squares in only one way, i.e., 790115881 + 655616025 = 28109^2 + 25605^2 .

It is not an unprimeable number, because it can be changed into a prime (1445731909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 361432975 + ... + 361432978.

Almost surely, 2^1445731906 is an apocalyptic number.

1445731906 is a deficient number, since it is larger than the sum of its proper divisors (722865956).

1445731906 is an equidigital number, since it uses as much as digits as its factorization.

1445731906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 722865955.

The product of its (nonzero) digits is 90720, while the sum is 40.

The square root of 1445731906 is about 38022.7814079928. The cubic root of 1445731906 is about 1130.7395649395.

The spelling of 1445731906 in words is "one billion, four hundred forty-five million, seven hundred thirty-one thousand, nine hundred six".