661632625263516 has 24 divisors (see below), whose sum is σ = 1559094701118864. Its totient is φ = 218360602396800.

The previous prime is 661632625263503. The next prime is 661632625263521. The reversal of 661632625263516 is 615362526236166.

It is a self number, because there is not a number n which added to its sum of digits gives 661632625263516.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 272950751785 + ... + 272950754208.

It is an arithmetic number, because the mean of its divisors is an integer number (64962279213286).

Almost surely, 2^{661632625263516} is an apocalyptic number.

It is an amenable number.

661632625263516 is an abundant number, since it is smaller than the sum of its proper divisors (897462075855348).

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

661632625263516 is a wasteful number, since it uses less digits than its factorization.

661632625263516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 545901506101 (or 545901506099 counting only the distinct ones).

The product of its digits is 83980800, while the sum is 60.

The spelling of 661632625263516 in words is "six hundred sixty-one trillion, six hundred thirty-two billion, six hundred twenty-five million, two hundred sixty-three thousand, five hundred sixteen".