155665049 has 2 divisors, whose sum is σ = 155665050. Its totient is φ = 155665048.

The previous prime is 155665021. The next prime is 155665051. The reversal of 155665049 is 940566551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 155251600 + 413449 = 12460^2 + 643^2 .

It is a cyclic number.

It is not a de Polignac number, because 155665049 - 2⁸ = 155664793 is a prime.

Together with 155665051, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 155664997 and 155665015.

It is not a weakly prime, because it can be changed into another prime (155665009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77832524 + 77832525.

It is an arithmetic number, because the mean of its divisors is an integer number (77832525).

Almost surely, 2^155665049 is an apocalyptic number.

It is an amenable number.

155665049 is a deficient number, since it is larger than the sum of its proper divisors (1).

155665049 is an equidigital number, since it uses as much as digits as its factorization.

155665049 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162000, while the sum is 41.

The square root of 155665049 is about 12476.5800201818. The cubic root of 155665049 is about 537.9357046938.

The spelling of 155665049 in words is "one hundred fifty-five million, six hundred sixty-five thousand, forty-nine".