39999945 has 8 divisors (see below), whose sum is σ = 63999936. Its totient is φ = 21333296.

The previous prime is 39999943. The next prime is 39999979. The reversal of 39999945 is 54999993.

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

It is a cyclic number.

It is not a de Polignac number, because 39999945 - 2¹ = 39999943 is a prime.

It is not an unprimeable number, because it can be changed into a prime (39999943) 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, 1333317 + ... + 1333346.

It is an arithmetic number, because the mean of its divisors is an integer number (7999992).

Almost surely, 2^39999945 is an apocalyptic number.

It is an amenable number.

39999945 is a deficient number, since it is larger than the sum of its proper divisors (23999991).

39999945 is a wasteful number, since it uses less digits than its factorization.

39999945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2666671.

The product of its digits is 3542940, while the sum is 57.

The square root of 39999945 is about 6324.5509722035. The cubic root of 39999945 is about 341.9950325875.

The spelling of 39999945 in words is "thirty-nine million, nine hundred ninety-nine thousand, nine hundred forty-five".