661241216 has 16 divisors (see below), whose sum is σ = 1317316740. Its totient is φ = 330620544.

The previous prime is 661241183. The next prime is 661241263. The reversal of 661241216 is 612142166.

661241216 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (16).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2582846 + ... + 2583101.

Almost surely, 2^661241216 is an apocalyptic number.

It is an amenable number.

661241216 is a deficient number, since it is larger than the sum of its proper divisors (656075524).

661241216 is an equidigital number, since it uses as much as digits as its factorization.

661241216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5165961 (or 5165949 counting only the distinct ones).

The product of its digits is 3456, while the sum is 29.

The square root of 661241216 is about 25714.6109439750. The cubic root of 661241216 is about 871.2042230826.

The spelling of 661241216 in words is "six hundred sixty-one million, two hundred forty-one thousand, two hundred sixteen".