39649905 has 40 divisors (see below), whose sum is σ = 72623232. Its totient is φ = 20686752.

The previous prime is 39649871. The next prime is 39649919. The reversal of 39649905 is 50994693.

It is a happy number.

It is not a de Polignac number, because 39649905 - 2²⁵ = 6095473 is a prime.

It is a super-2 number, since 2×39649905² = 3144229933018050, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

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 39 ways as a sum of consecutive naturals, for example, 17994 + ... + 20076.

Almost surely, 2^39649905 is an apocalyptic number.

It is an amenable number.

39649905 is a deficient number, since it is larger than the sum of its proper divisors (32973327).

39649905 is a wasteful number, since it uses less digits than its factorization.

39649905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2147 (or 2138 counting only the distinct ones).

The product of its (nonzero) digits is 262440, while the sum is 45.

The square root of 39649905 is about 6296.8170530832. The cubic root of 39649905 is about 340.9945074694.

The spelling of 39649905 in words is "thirty-nine million, six hundred forty-nine thousand, nine hundred five".