20387339677 has 4 divisors (see below), whose sum is σ = 21090351420. Its totient is φ = 19684327936.

The previous prime is 20387339669. The next prime is 20387339741. The reversal of 20387339677 is 77693378302.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 77693378302 = 2 ⋅38846689151.

It can be written as a sum of positive squares in 2 ways, for example, as 5576206276 + 14811133401 = 74674^2 + 121701^2 .

It is a cyclic number.

It is not a de Polignac number, because 20387339677 - 2³ = 20387339669 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20387399677) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 351505828 + ... + 351505885.

It is an arithmetic number, because the mean of its divisors is an integer number (5272587855).

Almost surely, 2^20387339677 is an apocalyptic number.

It is an amenable number.

20387339677 is a deficient number, since it is larger than the sum of its proper divisors (703011743).

20387339677 is an equidigital number, since it uses as much as digits as its factorization.

20387339677 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 703011742.

The product of its (nonzero) digits is 8001504, while the sum is 55.

The spelling of 20387339677 in words is "twenty billion, three hundred eighty-seven million, three hundred thirty-nine thousand, six hundred seventy-seven".