665216642 has 8 divisors (see below), whose sum is σ = 1007512896. Its totient is φ = 329379012.

The previous prime is 665216567. The next prime is 665216653. The reversal of 665216642 is 246612566.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 665216596 and 665216605.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1614398 + ... + 1614809.

It is an arithmetic number, because the mean of its divisors is an integer number (125939112).

Almost surely, 2^665216642 is an apocalyptic number.

665216642 is a deficient number, since it is larger than the sum of its proper divisors (342296254).

665216642 is a wasteful number, since it uses less digits than its factorization.

665216642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3229312.

The product of its digits is 103680, while the sum is 38.

The square root of 665216642 is about 25791.7940826147. The cubic root of 665216642 is about 872.9466483782.

The spelling of 665216642 in words is "six hundred sixty-five million, two hundred sixteen thousand, six hundred forty-two".