138768401 has 4 divisors (see below), whose sum is σ = 140669412. Its totient is φ = 136867392.

The previous prime is 138768397. The next prime is 138768403. The reversal of 138768401 is 104867831.

It is a Cunningham number, because it is equal to 11780²+1.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 78783376 + 59985025 = 8876^2 + 7745^2 .

It is a cyclic number.

It is not a de Polignac number, because 138768401 - 2² = 138768397 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (138768403) 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, 950396 + ... + 950541.

It is an arithmetic number, because the mean of its divisors is an integer number (35167353).

Almost surely, 2^138768401 is an apocalyptic number.

It is an amenable number.

138768401 is a deficient number, since it is larger than the sum of its proper divisors (1901011).

138768401 is an equidigital number, since it uses as much as digits as its factorization.

138768401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1901010.

The product of its (nonzero) digits is 32256, while the sum is 38.

The square root of 138768401 is about 11780.0000424448. Note that the first 4 decimals coincide. The cubic root of 138768401 is about 517.7222874464.

The spelling of 138768401 in words is "one hundred thirty-eight million, seven hundred sixty-eight thousand, four hundred one".