745038721 has 16 divisors (see below), whose sum is σ = 862185600. Its totient is φ = 630604800.

The previous prime is 745038709. The next prime is 745038733. The reversal of 745038721 is 127830547.

It is an interprime number because it is at equal distance from previous prime (745038709) and next prime (745038733).

It is not a de Polignac number, because 745038721 - 2¹³ = 745030529 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (745038751) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 316270 + ... + 318616.

It is an arithmetic number, because the mean of its divisors is an integer number (53886600).

Almost surely, 2^745038721 is an apocalyptic number.

It is an amenable number.

745038721 is a deficient number, since it is larger than the sum of its proper divisors (117146879).

745038721 is a wasteful number, since it uses less digits than its factorization.

745038721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2904.

The product of its (nonzero) digits is 47040, while the sum is 37.

The square root of 745038721 is about 27295.3974325343. The cubic root of 745038721 is about 906.5524754513.

The spelling of 745038721 in words is "seven hundred forty-five million, thirty-eight thousand, seven hundred twenty-one".