138342820 has 48 divisors (see below), whose sum is σ = 362210688. Its totient is φ = 43119360.

The previous prime is 138342817. The next prime is 138342829. The reversal of 138342820 is 28243831.

138342820 is digitally balanced in base 2, base 3 and base 9, because in such bases it contains all the possibile digits an equal number of times.

138342820 is strictly pandigital in base 9.

It is not an unprimeable number, because it can be changed into a prime (138342829) 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, 43377 + ... + 46456.

It is an arithmetic number, because the mean of its divisors is an integer number (7546056).

Almost surely, 2^138342820 is an apocalyptic number.

138342820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138342820 is an abundant number, since it is smaller than the sum of its proper divisors (223867868).

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

138342820 is a wasteful number, since it uses less digits than its factorization.

138342820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89860 (or 89858 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 31.

The square root of 138342820 is about 11761.9224619107. The cubic root of 138342820 is about 517.1924876893.

The spelling of 138342820 in words is "one hundred thirty-eight million, three hundred forty-two thousand, eight hundred twenty".