20749543107 has 4 divisors (see below), whose sum is σ = 27666057480. Its totient is φ = 13833028736.

The previous prime is 20749543099. The next prime is 20749543117. The reversal of 20749543107 is 70134594702.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20749543107 - 2³ = 20749543099 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20749543117) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3458257182 + ... + 3458257187.

It is an arithmetic number, because the mean of its divisors is an integer number (6916514370).

Almost surely, 2^20749543107 is an apocalyptic number.

20749543107 is a deficient number, since it is larger than the sum of its proper divisors (6916514373).

20749543107 is an equidigital number, since it uses as much as digits as its factorization.

20749543107 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6916514372.

The product of its (nonzero) digits is 211680, while the sum is 42.

The spelling of 20749543107 in words is "twenty billion, seven hundred forty-nine million, five hundred forty-three thousand, one hundred seven".