661525341646 has 48 divisors (see below), whose sum is σ = 1078314722208. Its totient is φ = 304234444800.

The previous prime is 661525341629. The next prime is 661525341649. The reversal of 661525341646 is 646143525166.

It is a self number, because there is not a number n which added to its sum of digits gives 661525341646.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661525341649) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 125262526 + ... + 125267806.

It is an arithmetic number, because the mean of its divisors is an integer number (22464890046).

Almost surely, 2^661525341646 is an apocalyptic number.

661525341646 is a deficient number, since it is larger than the sum of its proper divisors (416789380562).

661525341646 is a wasteful number, since it uses less digits than its factorization.

661525341646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6557 (or 6544 counting only the distinct ones).

The product of its digits is 3110400, while the sum is 49.

The spelling of 661525341646 in words is "six hundred sixty-one billion, five hundred twenty-five million, three hundred forty-one thousand, six hundred forty-six".