39897905 has 4 divisors (see below), whose sum is σ = 47877492. Its totient is φ = 31918320.

The previous prime is 39897883. The next prime is 39897911. The reversal of 39897905 is 50979893.

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 27836176 + 12061729 = 5276^2 + 3473^2 .

It is not a de Polignac number, because 39897905 - 2⁶ = 39897841 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 3989786 + ... + 3989795.

It is an arithmetic number, because the mean of its divisors is an integer number (11969373).

Almost surely, 2^39897905 is an apocalyptic number.

It is an amenable number.

39897905 is a deficient number, since it is larger than the sum of its proper divisors (7979587).

39897905 is an equidigital number, since it uses as much as digits as its factorization.

39897905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7979586.

The product of its (nonzero) digits is 612360, while the sum is 50.

The square root of 39897905 is about 6316.4788450528. The cubic root of 39897905 is about 341.7039747746.

The spelling of 39897905 in words is "thirty-nine million, eight hundred ninety-seven thousand, nine hundred five".