661347366241 has 4 divisors (see below), whose sum is σ = 661353224112. Its totient is φ = 661341508372.

The previous prime is 661347366209. The next prime is 661347366257. The reversal of 661347366241 is 142663743166.

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.

It is a cyclic number.

It is not a de Polignac number, because 661347366241 - 2⁵ = 661347366209 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (667347366241) 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, 2756191 + ... + 2986516.

It is an arithmetic number, because the mean of its divisors is an integer number (165338306028).

Almost surely, 2^661347366241 is an apocalyptic number.

It is an amenable number.

661347366241 is a deficient number, since it is larger than the sum of its proper divisors (5857871).

661347366241 is a wasteful number, since it uses less digits than its factorization.

661347366241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5857870.

The product of its digits is 2612736, while the sum is 49.

The spelling of 661347366241 in words is "six hundred sixty-one billion, three hundred forty-seven million, three hundred sixty-six thousand, two hundred forty-one".