138210291 has 6 divisors (see below), whose sum is σ = 199637100. Its totient is φ = 92140188.

The previous prime is 138210287. The next prime is 138210337. The reversal of 138210291 is 192012831.

It is not a de Polignac number, because 138210291 - 2² = 138210287 is a prime.

It is not an unprimeable number, because it can be changed into a prime (138210251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7678341 + ... + 7678358.

It is an arithmetic number, because the mean of its divisors is an integer number (33272850).

Almost surely, 2^138210291 is an apocalyptic number.

138210291 is a deficient number, since it is larger than the sum of its proper divisors (61426809).

138210291 is a wasteful number, since it uses less digits than its factorization.

138210291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15356705 (or 15356702 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 138210291 is about 11756.2872965916. The cubic root of 138210291 is about 517.0272823866.

The spelling of 138210291 in words is "one hundred thirty-eight million, two hundred ten thousand, two hundred ninety-one".