72725409 has 6 divisors (see below), whose sum is σ = 105047826. Its totient is φ = 48483600.

The previous prime is 72725377. The next prime is 72725423. The reversal of 72725409 is 90452727.

It can be written as a sum of positive squares in only one way, i.e., 71774784 + 950625 = 8472^2 + 975^2 .

It is not a de Polignac number, because 72725409 - 2⁵ = 72725377 is a prime.

It is a super-2 number, since 2×72725409² = 10577970228434562, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (72725449) 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 5 ways as a sum of consecutive naturals, for example, 4040292 + ... + 4040309.

It is an arithmetic number, because the mean of its divisors is an integer number (17507971).

Almost surely, 2^72725409 is an apocalyptic number.

It is an amenable number.

72725409 is a deficient number, since it is larger than the sum of its proper divisors (32322417).

72725409 is a wasteful number, since it uses less digits than its factorization.

72725409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8080607 (or 8080604 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 36.

The square root of 72725409 is about 8527.9193828272. The cubic root of 72725409 is about 417.4092388792.

The spelling of 72725409 in words is "seventy-two million, seven hundred twenty-five thousand, four hundred nine".