138564473 has 4 divisors (see below), whose sum is σ = 145857360. Its totient is φ = 131271588.

The previous prime is 138564463. The next prime is 138564521. The reversal of 138564473 is 374465831.

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 138564473 - 2⁴ = 138564457 is a prime.

It is a super-2 number, since 2×138564473² = 38400226355535458, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 138564473.

It is not an unprimeable number, because it can be changed into a prime (138564463) 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, 3646415 + ... + 3646452.

It is an arithmetic number, because the mean of its divisors is an integer number (36464340).

Almost surely, 2^138564473 is an apocalyptic number.

It is an amenable number.

138564473 is a deficient number, since it is larger than the sum of its proper divisors (7292887).

138564473 is an equidigital number, since it uses as much as digits as its factorization.

138564473 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7292886.

The product of its digits is 241920, while the sum is 41.

The square root of 138564473 is about 11771.3411725258. The cubic root of 138564473 is about 517.4685557376.

The spelling of 138564473 in words is "one hundred thirty-eight million, five hundred sixty-four thousand, four hundred seventy-three".