155330993 has 2 divisors, whose sum is σ = 155330994. Its totient is φ = 155330992.

The previous prime is 155330963. The next prime is 155330999. The reversal of 155330993 is 399033551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 155326369 + 4624 = 12463^2 + 68^2 .

It is a cyclic number.

It is not a de Polignac number, because 155330993 - 2¹⁶ = 155265457 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (155330999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77665496 + 77665497.

It is an arithmetic number, because the mean of its divisors is an integer number (77665497).

Almost surely, 2^155330993 is an apocalyptic number.

It is an amenable number.

155330993 is a deficient number, since it is larger than the sum of its proper divisors (1).

155330993 is an equidigital number, since it uses as much as digits as its factorization.

155330993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 54675, while the sum is 38.

The square root of 155330993 is about 12463.1855077263. The cubic root of 155330993 is about 537.5506271404.

The spelling of 155330993 in words is "one hundred fifty-five million, three hundred thirty thousand, nine hundred ninety-three".