720537641 has 4 divisors (see below), whose sum is σ = 720802500. Its totient is φ = 720272784.

The previous prime is 720537637. The next prime is 720537647. The reversal of 720537641 is 146735027.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 146735027 = 863 ⋅170029.

It can be written as a sum of positive squares in 2 ways, for example, as 199374400 + 521163241 = 14120^2 + 22829^2 .

It is a cyclic number.

It is not a de Polignac number, because 720537641 - 2² = 720537637 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (720537647) 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 in 3 ways as a sum of consecutive naturals, for example, 128306 + ... + 133803.

It is an arithmetic number, because the mean of its divisors is an integer number (180200625).

Almost surely, 2^720537641 is an apocalyptic number.

It is an amenable number.

720537641 is a deficient number, since it is larger than the sum of its proper divisors (264859).

720537641 is a wasteful number, since it uses less digits than its factorization.

720537641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 264858.

The product of its (nonzero) digits is 35280, while the sum is 35.

The square root of 720537641 is about 26842.8322089902. The cubic root of 720537641 is about 896.5039851876.

The spelling of 720537641 in words is "seven hundred twenty million, five hundred thirty-seven thousand, six hundred forty-one".