138420105 has 16 divisors (see below), whose sum is σ = 221928000. Its totient is φ = 73672128.

The previous prime is 138420101. The next prime is 138420133. The reversal of 138420105 is 501024831.

It is not a de Polignac number, because 138420105 - 2² = 138420101 is a prime.

It is a super-2 number, since 2×138420105² = 38320250936422050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (138420101) 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, 1762 + ... + 16731.

It is an arithmetic number, because the mean of its divisors is an integer number (13870500).

Almost surely, 2^138420105 is an apocalyptic number.

138420105 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

138420105 is a deficient number, since it is larger than the sum of its proper divisors (83507895).

138420105 is a wasteful number, since it uses less digits than its factorization.

138420105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19000.

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 138420105 is about 11765.2073929872. The cubic root of 138420105 is about 517.2887793519.

Adding to 138420105 its reverse (501024831), we get a palindrome (639444936).

The spelling of 138420105 in words is "one hundred thirty-eight million, four hundred twenty thousand, one hundred five".