38931661 has 2 divisors, whose sum is σ = 38931662. Its totient is φ = 38931660.

The previous prime is 38931653. The next prime is 38931677. The reversal of 38931661 is 16613983.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 31147561 + 7784100 = 5581^2 + 2790^2 .

It is a cyclic number.

It is not a de Polignac number, because 38931661 - 2³ = 38931653 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 38931661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (38931961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19465830 + 19465831.

It is an arithmetic number, because the mean of its divisors is an integer number (19465831).

Almost surely, 2^38931661 is an apocalyptic number.

It is an amenable number.

38931661 is a deficient number, since it is larger than the sum of its proper divisors (1).

38931661 is an equidigital number, since it uses as much as digits as its factorization.

38931661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 23328, while the sum is 37.

The square root of 38931661 is about 6239.5241004423. The cubic root of 38931661 is about 338.9229498607.

The spelling of 38931661 in words is "thirty-eight million, nine hundred thirty-one thousand, six hundred sixty-one".