661982611 has 8 divisors (see below), whose sum is σ = 669395664. Its totient is φ = 654581760.

The previous prime is 661982603. The next prime is 661982617. The reversal of 661982611 is 116289166.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 661982611 - 2³ = 661982603 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (661982617) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 145491 + ... + 149971.

It is an arithmetic number, because the mean of its divisors is an integer number (83674458).

Almost surely, 2^661982611 is an apocalyptic number.

661982611 is a deficient number, since it is larger than the sum of its proper divisors (7413053).

661982611 is a wasteful number, since it uses less digits than its factorization.

661982611 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6101.

The product of its digits is 31104, while the sum is 40.

The square root of 661982611 is about 25729.0227369793. The cubic root of 661982611 is about 871.5297045102.

The spelling of 661982611 in words is "six hundred sixty-one million, nine hundred eighty-two thousand, six hundred eleven".