155664509 has 16 divisors (see below), whose sum is σ = 209005440. Its totient is φ = 111965760.

The previous prime is 155664503. The next prime is 155664539. The reversal of 155664509 is 905466551.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-155664509 is a prime.

It is a super-2 number, since 2×155664509² = 48462878724422162, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155664503) 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 in 15 ways as a sum of consecutive naturals, for example, 76754 + ... + 78755.

It is an arithmetic number, because the mean of its divisors is an integer number (13062840).

Almost surely, 2^155664509 is an apocalyptic number.

It is an amenable number.

155664509 is a deficient number, since it is larger than the sum of its proper divisors (53340931).

155664509 is a wasteful number, since it uses less digits than its factorization.

155664509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155540.

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

The square root of 155664509 is about 12476.5583796174. The cubic root of 155664509 is about 537.9350826625.

The spelling of 155664509 in words is "one hundred fifty-five million, six hundred sixty-four thousand, five hundred nine".