725515377221 has 4 divisors (see below), whose sum is σ = 727991539212. Its totient is φ = 723039215232.

The previous prime is 725515377211. The next prime is 725515377253. The reversal of 725515377221 is 122773515527.

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 688078545025 + 37436832196 = 829505^2 + 193486^2 .

It is a cyclic number.

It is not a de Polignac number, because 725515377221 - 2⁶ = 725515377157 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (725515377211) 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 in 3 ways as a sum of consecutive naturals, for example, 1238080556 + ... + 1238081141.

It is an arithmetic number, because the mean of its divisors is an integer number (181997884803).

Almost surely, 2^725515377221 is an apocalyptic number.

It is an amenable number.

725515377221 is a deficient number, since it is larger than the sum of its proper divisors (2476161991).

725515377221 is a wasteful number, since it uses less digits than its factorization.

725515377221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2476161990.

The product of its digits is 1029000, while the sum is 47.

The spelling of 725515377221 in words is "seven hundred twenty-five billion, five hundred fifteen million, three hundred seventy-seven thousand, two hundred twenty-one".