664742473 has 2 divisors, whose sum is σ = 664742474. Its totient is φ = 664742472.

The previous prime is 664742467. The next prime is 664742489. The reversal of 664742473 is 374247466.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 425514384 + 239228089 = 20628^2 + 15467^2 .

It is a cyclic number.

It is not a de Polignac number, because 664742473 - 2²⁹ = 127871561 is a prime.

It is not a weakly prime, because it can be changed into another prime (664742423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332371236 + 332371237.

It is an arithmetic number, because the mean of its divisors is an integer number (332371237).

Almost surely, 2^664742473 is an apocalyptic number.

It is an amenable number.

664742473 is a deficient number, since it is larger than the sum of its proper divisors (1).

664742473 is an equidigital number, since it uses as much as digits as its factorization.

664742473 is an evil number, because the sum of its binary digits is even.

The product of its digits is 677376, while the sum is 43.

The square root of 664742473 is about 25782.6001985835. The cubic root of 664742473 is about 872.7391858258.

The spelling of 664742473 in words is "six hundred sixty-four million, seven hundred forty-two thousand, four hundred seventy-three".