20893965639 has 4 divisors (see below), whose sum is σ = 27858620856. Its totient is φ = 13929310424.

The previous prime is 20893965623. The next prime is 20893965643. The reversal of 20893965639 is 93656939802.

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 20893965639 - 2⁴ = 20893965623 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20893965539) 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, 3482327604 + ... + 3482327609.

It is an arithmetic number, because the mean of its divisors is an integer number (6964655214).

Almost surely, 2^20893965639 is an apocalyptic number.

20893965639 is a deficient number, since it is larger than the sum of its proper divisors (6964655217).

20893965639 is an equidigital number, since it uses as much as digits as its factorization.

20893965639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6964655216.

The product of its (nonzero) digits is 18895680, while the sum is 60.

The spelling of 20893965639 in words is "twenty billion, eight hundred ninety-three million, nine hundred sixty-five thousand, six hundred thirty-nine".