138717420 has 24 divisors (see below), whose sum is σ = 388408944. Its totient is φ = 36991296.

The previous prime is 138717367. The next prime is 138717421. The reversal of 138717420 is 24717831.

It is a happy number.

It is a super-2 number, since 2×138717420² = 38485045222912800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (138717421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1155919 + ... + 1156038.

It is an arithmetic number, because the mean of its divisors is an integer number (16183706).

Almost surely, 2^138717420 is an apocalyptic number.

138717420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138717420 is an abundant number, since it is smaller than the sum of its proper divisors (249691524).

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

138717420 is a wasteful number, since it uses less digits than its factorization.

138717420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2311969 (or 2311967 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 33.

The square root of 138717420 is about 11777.8359642169. The cubic root of 138717420 is about 517.6588790801.

The spelling of 138717420 in words is "one hundred thirty-eight million, seven hundred seventeen thousand, four hundred twenty".