138839090 has 32 divisors (see below), whose sum is σ = 269737776. Its totient is φ = 51148800.

The previous prime is 138839087. The next prime is 138839093. The reversal of 138839090 is 90938831.

It is a Cunningham number, because it is equal to 11783²+1.

It is an interprime number because it is at equal distance from previous prime (138839087) and next prime (138839093).

It can be written as a sum of positive squares in 8 ways, for example, as 18037009 + 120802081 = 4247^2 + 10991^2 .

It is not an unprimeable number, because it can be changed into a prime (138839093) 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, 76190 + ... + 77990.

Almost surely, 2^138839090 is an apocalyptic number.

138839090 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

138839090 is a deficient number, since it is larger than the sum of its proper divisors (130898686).

138839090 is a wasteful number, since it uses less digits than its factorization.

138839090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2414.

The product of its (nonzero) digits is 46656, while the sum is 41.

The square root of 138839090 is about 11783.0000424340. Note that the first 4 decimals coincide. The cubic root of 138839090 is about 517.8101822362.

The spelling of 138839090 in words is "one hundred thirty-eight million, eight hundred thirty-nine thousand, ninety".