39899561 has 8 divisors (see below), whose sum is σ = 45496584. Its totient is φ = 34663680.

The previous prime is 39899543. The next prime is 39899567. The reversal of 39899561 is 16599893.

It can be written as a sum of positive squares in 4 ways, for example, as 912025 + 38987536 = 955^2 + 6244^2 .

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-39899561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (39899567) 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 in 7 ways as a sum of consecutive naturals, for example, 90050 + ... + 90491.

It is an arithmetic number, because the mean of its divisors is an integer number (5687073).

Almost surely, 2^39899561 is an apocalyptic number.

It is an amenable number.

39899561 is a deficient number, since it is larger than the sum of its proper divisors (5597023).

39899561 is a wasteful number, since it uses less digits than its factorization.

39899561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180571.

The product of its digits is 524880, while the sum is 50.

The square root of 39899561 is about 6316.6099293846. The cubic root of 39899561 is about 341.7087022906.

The spelling of 39899561 in words is "thirty-nine million, eight hundred ninety-nine thousand, five hundred sixty-one".