670439521 has 2 divisors, whose sum is σ = 670439522. Its totient is φ = 670439520.

The previous prime is 670439461. The next prime is 670439527. The reversal of 670439521 is 125934076.

670439521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 588790225 + 81649296 = 24265^2 + 9036^2 .

It is a cyclic number.

It is not a de Polignac number, because 670439521 - 2¹⁷ = 670308449 is a prime.

It is not a weakly prime, because it can be changed into another prime (670439527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 335219760 + 335219761.

It is an arithmetic number, because the mean of its divisors is an integer number (335219761).

Almost surely, 2^670439521 is an apocalyptic number.

It is an amenable number.

670439521 is a deficient number, since it is larger than the sum of its proper divisors (1).

670439521 is an equidigital number, since it uses as much as digits as its factorization.

670439521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 45360, while the sum is 37.

The square root of 670439521 is about 25892.8469079783. The cubic root of 670439521 is about 875.2253116646.

Subtracting from 670439521 its reverse (125934076), we obtain a palindrome (544505445).

It can be divided in two parts, 6704 and 39521, that added together give a square (46225 = 215²).

The spelling of 670439521 in words is "six hundred seventy million, four hundred thirty-nine thousand, five hundred twenty-one".