661083660229 has 2 divisors, whose sum is σ = 661083660230. Its totient is φ = 661083660228.

The previous prime is 661083660221. The next prime is 661083660239. The reversal of 661083660229 is 922066380166.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 398253131329 + 262830528900 = 631073^2 + 512670^2 .

It is a cyclic number.

It is not a de Polignac number, because 661083660229 - 2³ = 661083660221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (661083660221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330541830114 + 330541830115.

It is an arithmetic number, because the mean of its divisors is an integer number (330541830115).

Almost surely, 2^661083660229 is an apocalyptic number.

It is an amenable number.

661083660229 is a deficient number, since it is larger than the sum of its proper divisors (1).

661083660229 is an equidigital number, since it uses as much as digits as its factorization.

661083660229 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1119744, while the sum is 49.

The spelling of 661083660229 in words is "six hundred sixty-one billion, eighty-three million, six hundred sixty thousand, two hundred twenty-nine".