155906449 has 2 divisors, whose sum is σ = 155906450. Its totient is φ = 155906448.

The previous prime is 155906441. The next prime is 155906479. The reversal of 155906449 is 944609551.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 154132225 + 1774224 = 12415^2 + 1332^2 .

It is an emirp because it is prime and its reverse (944609551) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 155906449 - 2³ = 155906441 is a prime.

It is equal to p_8757664 and since 155906449 and 8757664 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (155906441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77953224 + 77953225.

It is an arithmetic number, because the mean of its divisors is an integer number (77953225).

Almost surely, 2^155906449 is an apocalyptic number.

It is an amenable number.

155906449 is a deficient number, since it is larger than the sum of its proper divisors (1).

155906449 is an equidigital number, since it uses as much as digits as its factorization.

155906449 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 194400, while the sum is 43.

The square root of 155906449 is about 12486.2503979377. The cubic root of 155906449 is about 538.2136318017.

The spelling of 155906449 in words is "one hundred fifty-five million, nine hundred six thousand, four hundred forty-nine".