72046409 has 4 divisors (see below), whose sum is σ = 72137604. Its totient is φ = 71955216.

The previous prime is 72046399. The next prime is 72046421. The reversal of 72046409 is 90464027.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 90464027 = 1873 ⋅48299.

It can be written as a sum of positive squares in 2 ways, for example, as 11751184 + 60295225 = 3428^2 + 7765^2 .

It is a cyclic number.

It is not a de Polignac number, because 72046409 - 2⁴ = 72046393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72046439) 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, 44402 + ... + 45995.

It is an arithmetic number, because the mean of its divisors is an integer number (18034401).

Almost surely, 2^72046409 is an apocalyptic number.

It is an amenable number.

72046409 is a deficient number, since it is larger than the sum of its proper divisors (91195).

72046409 is an equidigital number, since it uses as much as digits as its factorization.

72046409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91194.

The product of its (nonzero) digits is 12096, while the sum is 32.

The square root of 72046409 is about 8488.0156102590. The cubic root of 72046409 is about 416.1061293108.

The spelling of 72046409 in words is "seventy-two million, forty-six thousand, four hundred nine".