138246408 has 24 divisors (see below), whose sum is σ = 374417550. Its totient is φ = 46082112.

The previous prime is 138246401. The next prime is 138246439. The reversal of 138246408 is 804642831.

138246408 is a `hidden beast` number, since 1 + 3 + 8 + 2 + 4 + 640 + 8 = 666.

It can be written as a sum of positive squares in only one way, i.e., 135070884 + 3175524 = 11622^2 + 1782^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×138246408² = 38224138649804928, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (138246401) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 959973 + ... + 960116.

Almost surely, 2^138246408 is an apocalyptic number.

138246408 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

138246408 is an abundant number, since it is smaller than the sum of its proper divisors (236171142).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

138246408 is a wasteful number, since it uses less digits than its factorization.

138246408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1920101 (or 1920094 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The square root of 138246408 is about 11757.8232679353. The cubic root of 138246408 is about 517.0723148462.

The spelling of 138246408 in words is "one hundred thirty-eight million, two hundred forty-six thousand, four hundred eight".