39891905907 has 32 divisors (see below), whose sum is σ = 60989829120. Its totient is φ = 22719684000.

The previous prime is 39891905899. The next prime is 39891905923. The reversal of 39891905907 is 70950919893.

It is not a de Polignac number, because 39891905907 - 2³ = 39891905899 is a prime.

It is not an unprimeable number, because it can be changed into a prime (39891905947) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12269032 + ... + 12272282.

It is an arithmetic number, because the mean of its divisors is an integer number (1905932160).

Almost surely, 2^39891905907 is an apocalyptic number.

39891905907 is a deficient number, since it is larger than the sum of its proper divisors (21097923213).

39891905907 is a wasteful number, since it uses less digits than its factorization.

39891905907 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5023.

The product of its (nonzero) digits is 5511240, while the sum is 60.

The spelling of 39891905907 in words is "thirty-nine billion, eight hundred ninety-one million, nine hundred five thousand, nine hundred seven".