381385509 has 16 divisors (see below), whose sum is σ = 522718272. Its totient is φ = 247240448.

The previous prime is 381385489. The next prime is 381385513. The reversal of 381385509 is 905583183.

It is a cyclic number.

It is not a de Polignac number, because 381385509 - 2⁸ = 381385253 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381385519) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7354 + ... + 28580.

It is an arithmetic number, because the mean of its divisors is an integer number (32669892).

Almost surely, 2^381385509 is an apocalyptic number.

It is an amenable number.

381385509 is a deficient number, since it is larger than the sum of its proper divisors (141332763).

381385509 is a wasteful number, since it uses less digits than its factorization.

381385509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21396.

The product of its (nonzero) digits is 129600, while the sum is 42.

The square root of 381385509 is about 19529.0939113928. The cubic root of 381385509 is about 725.1948799937.

The spelling of 381385509 in words is "three hundred eighty-one million, three hundred eighty-five thousand, five hundred nine".