138220497 has 12 divisors (see below), whose sum is σ = 210160080. Its totient is φ = 87297048.

The previous prime is 138220483. The next prime is 138220513. The reversal of 138220497 is 794022831.

It is not a de Polignac number, because 138220497 - 2²⁴ = 121443281 is a prime.

It is not an unprimeable number, because it can be changed into a prime (138220097) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 403983 + ... + 404324.

It is an arithmetic number, because the mean of its divisors is an integer number (17513340).

Almost surely, 2^138220497 is an apocalyptic number.

It is an amenable number.

138220497 is a deficient number, since it is larger than the sum of its proper divisors (71939583).

138220497 is a wasteful number, since it uses less digits than its factorization.

138220497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 808332 (or 808329 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 138220497 is about 11756.7213541871. The cubic root of 138220497 is about 517.0400085267.

The spelling of 138220497 in words is "one hundred thirty-eight million, two hundred twenty thousand, four hundred ninety-seven".