12155409 has 24 divisors (see below), whose sum is σ = 20401472. Its totient is φ = 6829920.

The previous prime is 12155401. The next prime is 12155419. The reversal of 12155409 is 90455121.

12155409 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 12155409 - 2³ = 12155401 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12155401) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2262 + ... + 5424.

Almost surely, 2^12155409 is an apocalyptic number.

It is an amenable number.

12155409 is a deficient number, since it is larger than the sum of its proper divisors (8246063).

12155409 is a wasteful number, since it uses less digits than its factorization.

12155409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3237 (or 3234 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 27.

The square root of 12155409 is about 3486.4608129162. The cubic root of 12155409 is about 229.9269396175.

The spelling of 12155409 in words is "twelve million, one hundred fifty-five thousand, four hundred nine".