661613011 has 8 divisors (see below), whose sum is σ = 667895184. Its totient is φ = 655349760.

The previous prime is 661612999. The next prime is 661613033. The reversal of 661613011 is 110316166.

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 661613011 - 2¹⁵ = 661580243 is a prime.

It is a super-2 number, since 2×661613011² = 875463552648972242, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (661613081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 71211 + ... + 79963.

It is an arithmetic number, because the mean of its divisors is an integer number (83486898).

Almost surely, 2^661613011 is an apocalyptic number.

661613011 is a deficient number, since it is larger than the sum of its proper divisors (6282173).

661613011 is a wasteful number, since it uses less digits than its factorization.

661613011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9461.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 661613011 is about 25721.8391838531. The cubic root of 661613011 is about 871.3674760062.

Adding to 661613011 its reverse (110316166), we get a palindrome (771929177).

The spelling of 661613011 in words is "six hundred sixty-one million, six hundred thirteen thousand, eleven".