155564447 has 2 divisors, whose sum is σ = 155564448. Its totient is φ = 155564446.

The previous prime is 155564401. The next prime is 155564449. The reversal of 155564447 is 744465551.

It is a strong prime.

It is an emirp because it is prime and its reverse (744465551) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-155564447 is a prime.

Together with 155564449, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (155564449) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77782223 + 77782224.

It is an arithmetic number, because the mean of its divisors is an integer number (77782224).

Almost surely, 2^155564447 is an apocalyptic number.

155564447 is a deficient number, since it is larger than the sum of its proper divisors (1).

155564447 is an equidigital number, since it uses as much as digits as its factorization.

155564447 is an evil number, because the sum of its binary digits is even.

The product of its digits is 336000, while the sum is 41.

The square root of 155564447 is about 12472.5477349257. The cubic root of 155564447 is about 537.8197954162.

The spelling of 155564447 in words is "one hundred fifty-five million, five hundred sixty-four thousand, four hundred forty-seven".