138520797 has 16 divisors (see below), whose sum is σ = 190375680. Its totient is φ = 89543232.

The previous prime is 138520783. The next prime is 138520801. The reversal of 138520797 is 797025831.

It is not a de Polignac number, because 138520797 - 2²⁶ = 71411933 is a prime.

It is a super-2 number, since 2×138520797² = 38376022403030418, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138520717) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10863 + ... + 19875.

It is an arithmetic number, because the mean of its divisors is an integer number (11898480).

Almost surely, 2^138520797 is an apocalyptic number.

It is an amenable number.

138520797 is a deficient number, since it is larger than the sum of its proper divisors (51854883).

138520797 is a wasteful number, since it uses less digits than its factorization.

138520797 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9172.

The product of its (nonzero) digits is 105840, while the sum is 42.

The square root of 138520797 is about 11769.4858426356. The cubic root of 138520797 is about 517.4141807327.

The spelling of 138520797 in words is "one hundred thirty-eight million, five hundred twenty thousand, seven hundred ninety-seven".