20938346687 has 2 divisors, whose sum is σ = 20938346688. Its totient is φ = 20938346686.

The previous prime is 20938346659. The next prime is 20938346719. The reversal of 20938346687 is 78664383902.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20938346687 - 2¹⁶ = 20938281151 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20938346087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10469173343 + 10469173344.

It is an arithmetic number, because the mean of its divisors is an integer number (10469173344).

Almost surely, 2^20938346687 is an apocalyptic number.

20938346687 is a deficient number, since it is larger than the sum of its proper divisors (1).

20938346687 is an equidigital number, since it uses as much as digits as its factorization.

20938346687 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10450944, while the sum is 56.

The spelling of 20938346687 in words is "twenty billion, nine hundred thirty-eight million, three hundred forty-six thousand, six hundred eighty-seven".