661408530223 has 16 divisors (see below), whose sum is σ = 764176032256. Its totient is φ = 560724755040.

The previous prime is 661408530197. The next prime is 661408530239. The reversal of 661408530223 is 322035804166.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-661408530223 is a prime.

It is a super-2 number, since 2×661408530223² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661408530323) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19165 + ... + 1150297.

It is an arithmetic number, because the mean of its divisors is an integer number (47761002016).

Almost surely, 2^661408530223 is an apocalyptic number.

661408530223 is a deficient number, since it is larger than the sum of its proper divisors (102767502033).

661408530223 is a wasteful number, since it uses less digits than its factorization.

661408530223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1132054.

The product of its (nonzero) digits is 207360, while the sum is 40.

The spelling of 661408530223 in words is "six hundred sixty-one billion, four hundred eight million, five hundred thirty thousand, two hundred twenty-three".