672561409 has 8 divisors (see below), whose sum is σ = 741141632. Its totient is φ = 606387600.

The previous prime is 672561403. The next prime is 672561413. The reversal of 672561409 is 904165276.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 672561409 - 2³ = 672561401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (672561401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 601017 + ... + 602134.

It is an arithmetic number, because the mean of its divisors is an integer number (92642704).

Almost surely, 2^672561409 is an apocalyptic number.

It is an amenable number.

672561409 is a deficient number, since it is larger than the sum of its proper divisors (68580223).

672561409 is a wasteful number, since it uses less digits than its factorization.

672561409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1203207.

The product of its (nonzero) digits is 90720, while the sum is 40.

The square root of 672561409 is about 25933.7889441555. The cubic root of 672561409 is about 876.1476788791.

The spelling of 672561409 in words is "six hundred seventy-two million, five hundred sixty-one thousand, four hundred nine".