745887521 has 4 divisors (see below), whose sum is σ = 747835392. Its totient is φ = 743939652.

The previous prime is 745887491. The next prime is 745887533. The reversal of 745887521 is 125788547.

745887521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-745887521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (745887421) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 973361 + ... + 974126.

It is an arithmetic number, because the mean of its divisors is an integer number (186958848).

Almost surely, 2^745887521 is an apocalyptic number.

It is an amenable number.

745887521 is a deficient number, since it is larger than the sum of its proper divisors (1947871).

745887521 is a wasteful number, since it uses less digits than its factorization.

745887521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1947870.

The product of its digits is 627200, while the sum is 47.

The square root of 745887521 is about 27310.9414154840. The cubic root of 745887521 is about 906.8966140348.

The spelling of 745887521 in words is "seven hundred forty-five million, eight hundred eighty-seven thousand, five hundred twenty-one".