39881557 has 2 divisors, whose sum is σ = 39881558. Its totient is φ = 39881556.

The previous prime is 39881539. The next prime is 39881573. The reversal of 39881557 is 75518893.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 37466641 + 2414916 = 6121^2 + 1554^2 .

It is an emirp because it is prime and its reverse (75518893) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 39881557 - 2¹¹ = 39879509 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39881537) 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, 19940778 + 19940779.

It is an arithmetic number, because the mean of its divisors is an integer number (19940779).

Almost surely, 2^39881557 is an apocalyptic number.

It is an amenable number.

39881557 is a deficient number, since it is larger than the sum of its proper divisors (1).

39881557 is an equidigital number, since it uses as much as digits as its factorization.

39881557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 302400, while the sum is 46.

The square root of 39881557 is about 6315.1846370474. The cubic root of 39881557 is about 341.6572978064.

The spelling of 39881557 in words is "thirty-nine million, eight hundred eighty-one thousand, five hundred fifty-seven".