38809681 has 4 divisors (see below), whose sum is σ = 38834100. Its totient is φ = 38785264.

The previous prime is 38809637. The next prime is 38809697. The reversal of 38809681 is 18690883.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18690883 = 37 ⋅505159.

It can be written as a sum of positive squares in 2 ways, for example, as 2509056 + 36300625 = 1584^2 + 6025^2 .

It is a cyclic number.

It is not a de Polignac number, because 38809681 - 2¹³ = 38801489 is a prime.

It is a super-2 number, since 2×38809681² = 3012382678643522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (38809081) 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, 9646 + ... + 13063.

It is an arithmetic number, because the mean of its divisors is an integer number (9708525).

Almost surely, 2^38809681 is an apocalyptic number.

It is an amenable number.

38809681 is a deficient number, since it is larger than the sum of its proper divisors (24419).

38809681 is a wasteful number, since it uses less digits than its factorization.

38809681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24418.

The product of its (nonzero) digits is 82944, while the sum is 43.

The square root of 38809681 is about 6229.7416479337. The cubic root of 38809681 is about 338.5686103776.

The spelling of 38809681 in words is "thirty-eight million, eight hundred nine thousand, six hundred eighty-one".