155666647 has 2 divisors, whose sum is σ = 155666648. Its totient is φ = 155666646.

The previous prime is 155666633. The next prime is 155666669. The reversal of 155666647 is 746666551.

155666647 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 155666647 - 2¹¹ = 155664599 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 155666597 and 155666606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (155666347) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77833323 + 77833324.

It is an arithmetic number, because the mean of its divisors is an integer number (77833324).

Almost surely, 2^155666647 is an apocalyptic number.

155666647 is a deficient number, since it is larger than the sum of its proper divisors (1).

155666647 is an equidigital number, since it uses as much as digits as its factorization.

155666647 is an evil number, because the sum of its binary digits is even.

The product of its digits is 907200, while the sum is 46.

The square root of 155666647 is about 12476.6440600027. The cubic root of 155666647 is about 537.9375454374.

The spelling of 155666647 in words is "one hundred fifty-five million, six hundred sixty-six thousand, six hundred forty-seven".