661441013 has 4 divisors (see below), whose sum is σ = 661631040. Its totient is φ = 661250988.

The previous prime is 661441003. The next prime is 661441031. The reversal of 661441013 is 310144166.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 310144166 = 2 ⋅155072083.

It is a cyclic number.

It is not a de Polignac number, because 661441013 - 2¹² = 661436917 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661441003) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 89693 + ... + 96786.

It is an arithmetic number, because the mean of its divisors is an integer number (165407760).

Almost surely, 2^661441013 is an apocalyptic number.

It is an amenable number.

661441013 is a deficient number, since it is larger than the sum of its proper divisors (190027).

661441013 is a wasteful number, since it uses less digits than its factorization.

661441013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 190026.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 661441013 is about 25718.4955430912. The cubic root of 661441013 is about 871.2919603347.

Adding to 661441013 its reverse (310144166), we get a palindrome (971585179).

The spelling of 661441013 in words is "six hundred sixty-one million, four hundred forty-one thousand, thirteen".