665216522 has 4 divisors (see below), whose sum is σ = 997824786. Its totient is φ = 332608260.

The previous prime is 665216509. The next prime is 665216533. The reversal of 665216522 is 225612566.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 573075721 + 92140801 = 23939^2 + 9599^2 .

It is a super-2 number, since 2×665216522² = 885026042283552968, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 166304129 + ... + 166304132.

Almost surely, 2^665216522 is an apocalyptic number.

665216522 is a deficient number, since it is larger than the sum of its proper divisors (332608264).

665216522 is a wasteful number, since it uses less digits than its factorization.

665216522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 332608263.

The product of its digits is 43200, while the sum is 35.

The square root of 665216522 is about 25791.7917562933. The cubic root of 665216522 is about 872.9465958872.

The spelling of 665216522 in words is "six hundred sixty-five million, two hundred sixteen thousand, five hundred twenty-two".