487991173 has 2 divisors, whose sum is σ = 487991174. Its totient is φ = 487991172.

The previous prime is 487991159. The next prime is 487991221. The reversal of 487991173 is 371199784.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 305795169 + 182196004 = 17487^2 + 13498^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-487991173 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (487991473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 243995586 + 243995587.

It is an arithmetic number, because the mean of its divisors is an integer number (243995587).

Almost surely, 2^487991173 is an apocalyptic number.

It is an amenable number.

487991173 is a deficient number, since it is larger than the sum of its proper divisors (1).

487991173 is an equidigital number, since it uses as much as digits as its factorization.

487991173 is an evil number, because the sum of its binary digits is even.

The product of its digits is 381024, while the sum is 49.

The square root of 487991173 is about 22090.5222437135. The cubic root of 487991173 is about 787.2946896710.

The spelling of 487991173 in words is "four hundred eighty-seven million, nine hundred ninety-one thousand, one hundred seventy-three".