389138887 has 4 divisors (see below), whose sum is σ = 389229736. Its totient is φ = 389048040.

The previous prime is 389138861. The next prime is 389138899. The reversal of 389138887 is 788831983.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 389138887 - 2¹⁵ = 389106119 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (389138987) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38664 + ... + 47677.

It is an arithmetic number, because the mean of its divisors is an integer number (97307434).

Almost surely, 2^389138887 is an apocalyptic number.

389138887 is a deficient number, since it is larger than the sum of its proper divisors (90849).

389138887 is an equidigital number, since it uses as much as digits as its factorization.

389138887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90848.

The product of its digits is 2322432, while the sum is 55.

The square root of 389138887 is about 19726.6035343138. The cubic root of 389138887 is about 730.0762333598.

It can be divided in two parts, 3891 and 38887, that added together give a triangular number (42778 = T₂₉₂).

The spelling of 389138887 in words is "three hundred eighty-nine million, one hundred thirty-eight thousand, eight hundred eighty-seven".