672161257 has 8 divisors (see below), whose sum is σ = 699845832. Its totient is φ = 645014400.

The previous prime is 672161227. The next prime is 672161299. The reversal of 672161257 is 752161276.

It can be written as a sum of positive squares in 4 ways, for example, as 191850201 + 480311056 = 13851^2 + 21916^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-672161257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (672161207) 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 7 ways as a sum of consecutive naturals, for example, 131878 + ... + 136879.

It is an arithmetic number, because the mean of its divisors is an integer number (87480729).

Almost surely, 2^672161257 is an apocalyptic number.

It is an amenable number.

672161257 is a deficient number, since it is larger than the sum of its proper divisors (27684575).

672161257 is a wasteful number, since it uses less digits than its factorization.

672161257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 268859.

The product of its digits is 35280, while the sum is 37.

The square root of 672161257 is about 25926.0729189748. The cubic root of 672161257 is about 875.9738846874.

The spelling of 672161257 in words is "six hundred seventy-two million, one hundred sixty-one thousand, two hundred fifty-seven".