155105999 has 2 divisors, whose sum is σ = 155106000. Its totient is φ = 155105998.

The previous prime is 155105953. The next prime is 155106013. The reversal of 155105999 is 999501551.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 155105999 - 2²⁴ = 138328783 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (155105939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77552999 + 77553000.

It is an arithmetic number, because the mean of its divisors is an integer number (77553000).

Almost surely, 2^155105999 is an apocalyptic number.

155105999 is a deficient number, since it is larger than the sum of its proper divisors (1).

155105999 is an equidigital number, since it uses as much as digits as its factorization.

155105999 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 91125, while the sum is 44.

The square root of 155105999 is about 12454.1558927131. The cubic root of 155105999 is about 537.2909577588.

The spelling of 155105999 in words is "one hundred fifty-five million, one hundred five thousand, nine hundred ninety-nine".