745138649 has 2 divisors, whose sum is σ = 745138650. Its totient is φ = 745138648.

The previous prime is 745138609. The next prime is 745138651. The reversal of 745138649 is 946831547.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 660130249 + 85008400 = 25693^2 + 9220^2 .

It is a cyclic number.

It is not a de Polignac number, because 745138649 - 2²⁸ = 476703193 is a prime.

Together with 745138651, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (745138609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 372569324 + 372569325.

It is an arithmetic number, because the mean of its divisors is an integer number (372569325).

Almost surely, 2^745138649 is an apocalyptic number.

It is an amenable number.

745138649 is a deficient number, since it is larger than the sum of its proper divisors (1).

745138649 is an equidigital number, since it uses as much as digits as its factorization.

745138649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 725760, while the sum is 47.

The square root of 745138649 is about 27297.2278629168. The cubic root of 745138649 is about 906.5930039605.

The spelling of 745138649 in words is "seven hundred forty-five million, one hundred thirty-eight thousand, six hundred forty-nine".