661626611600 has 60 divisors (see below), whose sum is σ = 1609678997760. Its totient is φ = 261300624000.

The previous prime is 661626611563. The next prime is 661626611609. The reversal of 661626611600 is 6116626166.

It is not an unprimeable number, because it can be changed into a prime (661626611609) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10437176 + ... + 10500375.

It is an arithmetic number, because the mean of its divisors is an integer number (26827983296).

Almost surely, 2^661626611600 is an apocalyptic number.

It is an amenable number.

661626611600 is an abundant number, since it is smaller than the sum of its proper divisors (948052386160).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

661626611600 is a wasteful number, since it uses less digits than its factorization.

661626611600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20937648 (or 20937637 counting only the distinct ones).

The product of its (nonzero) digits is 93312, while the sum is 41.

The spelling of 661626611600 in words is "six hundred sixty-one billion, six hundred twenty-six million, six hundred eleven thousand, six hundred".