155198123 has 2 divisors, whose sum is σ = 155198124. Its totient is φ = 155198122.

The previous prime is 155198101. The next prime is 155198149. The reversal of 155198123 is 321891551.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 155198123 - 2¹⁰ = 155197099 is a prime.

It is not a weakly prime, because it can be changed into another prime (155198623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77599061 + 77599062.

It is an arithmetic number, because the mean of its divisors is an integer number (77599062).

Almost surely, 2^155198123 is an apocalyptic number.

155198123 is a deficient number, since it is larger than the sum of its proper divisors (1).

155198123 is an equidigital number, since it uses as much as digits as its factorization.

155198123 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10800, while the sum is 35.

The square root of 155198123 is about 12457.8538681428. The cubic root of 155198123 is about 537.3973099658.

The spelling of 155198123 in words is "one hundred fifty-five million, one hundred ninety-eight thousand, one hundred twenty-three".