627909720661 has 4 divisors (see below), whose sum is σ = 627911401612. Its totient is φ = 627908039712.

The previous prime is 627909720653. The next prime is 627909720709. The reversal of 627909720661 is 166027909726.

627909720661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

627909720661 is a nontrivial binomial coefficient, being equal to C(1120634, 2).

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

It can be written as a sum of positive squares in 2 ways, for example, as 258184918161 + 369724802500 = 508119^2 + 608050^2 .

It is a 3-Lehmer number, since φ(627909720661) divides (627909720661-1)³.

It is a cyclic number.

It is not a de Polignac number, because 627909720661 - 2³ = 627909720653 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (627909720461) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1 + ... + 1120633.

It is an arithmetic number, because the mean of its divisors is an integer number (156977850403).

It is a Poulet number, since it divides 2^627909720660-1.

Almost surely, 2^627909720661 is an apocalyptic number.

627909720661 is the 1120633-rd triangular number and also the 560317-th hexagonal number.

627909720661 is the 373545-th centered nonagonal number.

It is an amenable number.

627909720661 is a deficient number, since it is larger than the sum of its proper divisors (1680951).

627909720661 is a wasteful number, since it uses less digits than its factorization.

627909720661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1680950.

The product of its (nonzero) digits is 3429216, while the sum is 55.

The spelling of 627909720661 in words is "six hundred twenty-seven billion, nine hundred nine million, seven hundred twenty thousand, six hundred sixty-one".