2661666653389 has 2 divisors, whose sum is σ = 2661666653390. Its totient is φ = 2661666653388.

The previous prime is 2661666653363. The next prime is 2661666653411. The reversal of 2661666653389 is 9833566661662.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2655482089225 + 6184564164 = 1629565^2 + 78642^2 .

It is a cyclic number.

It is not a de Polignac number, because 2661666653389 - 2²³ = 2661658264781 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2661666653309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1330833326694 + 1330833326695.

It is an arithmetic number, because the mean of its divisors is an integer number (1330833326695).

Almost surely, 2^{2661666653389} is an apocalyptic number.

It is an amenable number.

2661666653389 is a deficient number, since it is larger than the sum of its proper divisors (1).

2661666653389 is an equidigital number, since it uses as much as digits as its factorization.

2661666653389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 302330880, while the sum is 67.

The spelling of 2661666653389 in words is "two trillion, six hundred sixty-one billion, six hundred sixty-six million, six hundred fifty-three thousand, three hundred eighty-nine".