138336261 has 24 divisors (see below), whose sum is σ = 215005824. Its totient is φ = 78886080.

The previous prime is 138336239. The next prime is 138336277. The reversal of 138336261 is 162633831.

It is not a de Polignac number, because 138336261 - 2⁶ = 138336197 is a prime.

It is a super-2 number, since 2×138336261² = 38273842214920242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138336761) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 133401 + ... + 134433.

It is an arithmetic number, because the mean of its divisors is an integer number (8958576).

Almost surely, 2^138336261 is an apocalyptic number.

It is an amenable number.

138336261 is a deficient number, since it is larger than the sum of its proper divisors (76669563).

138336261 is a wasteful number, since it uses less digits than its factorization.

138336261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1961 (or 1954 counting only the distinct ones).

The product of its digits is 15552, while the sum is 33.

The square root of 138336261 is about 11761.6436351388. The cubic root of 138336261 is about 517.1843139869.

The spelling of 138336261 in words is "one hundred thirty-eight million, three hundred thirty-six thousand, two hundred sixty-one".