725388161 has 4 divisors (see below), whose sum is σ = 732570324. Its totient is φ = 718206000.

The previous prime is 725388151. The next prime is 725388193. The reversal of 725388161 is 161883527.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 509856400 + 215531761 = 22580^2 + 14681^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-725388161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (725388101) 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, 3590930 + ... + 3591131.

It is an arithmetic number, because the mean of its divisors is an integer number (183142581).

Almost surely, 2^725388161 is an apocalyptic number.

It is an amenable number.

725388161 is a deficient number, since it is larger than the sum of its proper divisors (7182163).

725388161 is a wasteful number, since it uses less digits than its factorization.

725388161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7182162.

The product of its digits is 80640, while the sum is 41.

The square root of 725388161 is about 26933.0310399702. The cubic root of 725388161 is about 898.5111850045.

The spelling of 725388161 in words is "seven hundred twenty-five million, three hundred eighty-eight thousand, one hundred sixty-one".