38691643 has 8 divisors (see below), whose sum is σ = 41741568. Its totient is φ = 35727744.

The previous prime is 38691599. The next prime is 38691647. The reversal of 38691643 is 34619683.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-38691643 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 38691596 and 38691605.

It is not an unprimeable number, because it can be changed into a prime (38691647) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20571 + ... + 22372.

It is an arithmetic number, because the mean of its divisors is an integer number (5217696).

Almost surely, 2^38691643 is an apocalyptic number.

38691643 is a deficient number, since it is larger than the sum of its proper divisors (3049925).

38691643 is a wasteful number, since it uses less digits than its factorization.

38691643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43013.

The product of its digits is 93312, while the sum is 40.

The square root of 38691643 is about 6220.2606858555. The cubic root of 38691643 is about 338.2250144377.

It can be divided in two parts, 386 and 91643, that added together give a palindrome (92029).

The spelling of 38691643 in words is "thirty-eight million, six hundred ninety-one thousand, six hundred forty-three".