20091378249 has 6 divisors (see below), whose sum is σ = 29020879706. Its totient is φ = 13394252160.

The previous prime is 20091378211. The next prime is 20091378319. The reversal of 20091378249 is 94287319002.

It can be written as a sum of positive squares in only one way, i.e., 19594400400 + 496977849 = 139980^2 + 22293^2 .

It is not a de Polignac number, because 20091378249 - 2²⁹ = 19554507337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20091378149) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1116187672 + ... + 1116187689.

Almost surely, 2^20091378249 is an apocalyptic number.

It is an amenable number.

20091378249 is a deficient number, since it is larger than the sum of its proper divisors (8929501457).

20091378249 is a wasteful number, since it uses less digits than its factorization.

20091378249 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2232375367 (or 2232375364 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The spelling of 20091378249 in words is "twenty billion, ninety-one million, three hundred seventy-eight thousand, two hundred forty-nine".