138561097 has 4 divisors (see below), whose sum is σ = 138874320. Its totient is φ = 138247876.

The previous prime is 138561089. The next prime is 138561107. The reversal of 138561097 is 790165831.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 138561097 - 2³ = 138561089 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138561047) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 155947 + ... + 156832.

It is an arithmetic number, because the mean of its divisors is an integer number (34718580).

Almost surely, 2^138561097 is an apocalyptic number.

It is an amenable number.

138561097 is a deficient number, since it is larger than the sum of its proper divisors (313223).

138561097 is an equidigital number, since it uses as much as digits as its factorization.

138561097 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 313222.

The product of its (nonzero) digits is 45360, while the sum is 40.

The square root of 138561097 is about 11771.1977725294. The cubic root of 138561097 is about 517.4643531499.

The spelling of 138561097 in words is "one hundred thirty-eight million, five hundred sixty-one thousand, ninety-seven".