673973521 has 9 divisors (see below), whose sum is σ = 730171281. Its totient is φ = 621817872.

The previous prime is 673973519. The next prime is 673973581. The reversal of 673973521 is 125379376.

It is a happy number.

The square root of 673973521 is 25961.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 487923921 + 186049600 = 22089^2 + 13640^2 .

It is not a de Polignac number, because 673973521 - 2¹ = 673973519 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (673973581) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 336495 + ... + 338491.

Almost surely, 2^673973521 is an apocalyptic number.

673973521 is the 25961-st square number.

673973521 is the 12981-st centered octagonal number.

It is an amenable number.

673973521 is a deficient number, since it is larger than the sum of its proper divisors (56197760).

673973521 is an frugal number, since it uses more digits than its factorization.

673973521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4020 (or 2010 counting only the distinct ones).

The product of its digits is 238140, while the sum is 43.

The cubic root of 673973521 is about 876.7604376814.

The spelling of 673973521 in words is "six hundred seventy-three million, nine hundred seventy-three thousand, five hundred twenty-one".