665663722 has 4 divisors (see below), whose sum is σ = 998495586. Its totient is φ = 332831860.

The previous prime is 665663711. The next prime is 665663731. The reversal of 665663722 is 227366566.

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., 504855961 + 160807761 = 22469^2 + 12681^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 166415929 + ... + 166415932.

Almost surely, 2^665663722 is an apocalyptic number.

665663722 is a deficient number, since it is larger than the sum of its proper divisors (332831864).

665663722 is a wasteful number, since it uses less digits than its factorization.

665663722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 332831863.

The product of its digits is 544320, while the sum is 43.

The square root of 665663722 is about 25800.4597245863. The cubic root of 665663722 is about 873.1421684353.

The spelling of 665663722 in words is "six hundred sixty-five million, six hundred sixty-three thousand, seven hundred twenty-two".