20671767639 has 12 divisors (see below), whose sum is σ = 29861756496. Its totient is φ = 13780007712.

The previous prime is 20671767629. The next prime is 20671767671. The reversal of 20671767639 is 93676717602.

It is not a de Polignac number, because 20671767639 - 2⁷ = 20671767511 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20671767629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21979 + ... + 204515.

It is an arithmetic number, because the mean of its divisors is an integer number (2488479708).

Almost surely, 2^20671767639 is an apocalyptic number.

20671767639 is a deficient number, since it is larger than the sum of its proper divisors (9189988857).

20671767639 is a wasteful number, since it uses less digits than its factorization.

20671767639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195126 (or 195123 counting only the distinct ones).

The product of its (nonzero) digits is 4000752, while the sum is 54.

The spelling of 20671767639 in words is "twenty billion, six hundred seventy-one million, seven hundred sixty-seven thousand, six hundred thirty-nine".