138353220 has 36 divisors (see below), whose sum is σ = 419671980. Its totient is φ = 36894144.

The previous prime is 138353209. The next prime is 138353251. The reversal of 138353220 is 22353831.

It can be written as a sum of positive squares in 2 ways, for example, as 33454656 + 104898564 = 5784^2 + 10242^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×138353220² = 38283226968736800, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 384135 + ... + 384494.

It is an arithmetic number, because the mean of its divisors is an integer number (11657555).

Almost surely, 2^138353220 is an apocalyptic number.

138353220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138353220 is an abundant number, since it is smaller than the sum of its proper divisors (281318760).

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

138353220 is a wasteful number, since it uses less digits than its factorization.

138353220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 768644 (or 768639 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 138353220 is about 11762.3645582000. The cubic root of 138353220 is about 517.2054474442.

The spelling of 138353220 in words is "one hundred thirty-eight million, three hundred fifty-three thousand, two hundred twenty".