138806105 has 16 divisors (see below), whose sum is σ = 176806800. Its totient is φ = 104251392.

The previous prime is 138806051. The next prime is 138806117. The reversal of 138806105 is 501608831.

It can be written as a sum of positive squares in 8 ways, for example, as 4338889 + 134467216 = 2083^2 + 11596^2 .

It is a cyclic number.

It is not a de Polignac number, because 138806105 - 2¹² = 138802009 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36347 + ... + 39983.

It is an arithmetic number, because the mean of its divisors is an integer number (11050425).

Almost surely, 2^138806105 is an apocalyptic number.

It is an amenable number.

138806105 is a deficient number, since it is larger than the sum of its proper divisors (38000695).

138806105 is a wasteful number, since it uses less digits than its factorization.

138806105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4108.

The product of its (nonzero) digits is 5760, while the sum is 32.

The square root of 138806105 is about 11781.6002733075. The cubic root of 138806105 is about 517.7691723600.

The spelling of 138806105 in words is "one hundred thirty-eight million, eight hundred six thousand, one hundred five".