138217290 has 16 divisors (see below), whose sum is σ = 331721568. Its totient is φ = 36857936.

The previous prime is 138217279. The next prime is 138217297. The reversal of 138217290 is 92712831.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (138217297) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2303592 + ... + 2303651.

It is an arithmetic number, because the mean of its divisors is an integer number (20732598).

Almost surely, 2^138217290 is an apocalyptic number.

138217290 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

138217290 is an abundant number, since it is smaller than the sum of its proper divisors (193504278).

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

138217290 is a wasteful number, since it uses less digits than its factorization.

138217290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4607253.

The product of its (nonzero) digits is 6048, while the sum is 33.

The square root of 138217290 is about 11756.5849633301. The cubic root of 138217290 is about 517.0360096983.

The spelling of 138217290 in words is "one hundred thirty-eight million, two hundred seventeen thousand, two hundred ninety".