665010650621 has 16 divisors (see below), whose sum is σ = 706599696000. Its totient is φ = 624103144128.

The previous prime is 665010650609. The next prime is 665010650653. The reversal of 665010650621 is 126056010566.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-665010650621 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665010650921) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 741080 + ... + 1370846.

It is an arithmetic number, because the mean of its divisors is an integer number (44162481000).

Almost surely, 2^665010650621 is an apocalyptic number.

It is an amenable number.

665010650621 is a deficient number, since it is larger than the sum of its proper divisors (41589045379).

665010650621 is a wasteful number, since it uses less digits than its factorization.

665010650621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 630308.

The product of its (nonzero) digits is 64800, while the sum is 38.

The spelling of 665010650621 in words is "six hundred sixty-five billion, ten million, six hundred fifty thousand, six hundred twenty-one".