138262509 has 48 divisors (see below), whose sum is σ = 251057664. Its totient is φ = 71229600.

The previous prime is 138262507. The next prime is 138262541. The reversal of 138262509 is 905262831.

138262509 is a `hidden beast` number, since 13 + 82 + 62 + 509 = 666.

It is not a de Polignac number, because 138262509 - 2¹ = 138262507 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138262507) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 90022 + ... + 91544.

It is an arithmetic number, because the mean of its divisors is an integer number (5230368).

Almost surely, 2^138262509 is an apocalyptic number.

It is an amenable number.

138262509 is a deficient number, since it is larger than the sum of its proper divisors (112795155).

138262509 is a wasteful number, since it uses less digits than its factorization.

138262509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1678 (or 1675 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 138262509 is about 11758.5079410612. The cubic root of 138262509 is about 517.0923878407.

The spelling of 138262509 in words is "one hundred thirty-eight million, two hundred sixty-two thousand, five hundred nine".