20101978943 has 2 divisors, whose sum is σ = 20101978944. Its totient is φ = 20101978942.

The previous prime is 20101978927. The next prime is 20101978993. The reversal of 20101978943 is 34987910102.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20101978943 - 2⁴ = 20101978927 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20101978894 and 20101978903.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20101978993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10050989471 + 10050989472.

It is an arithmetic number, because the mean of its divisors is an integer number (10050989472).

Almost surely, 2^20101978943 is an apocalyptic number.

20101978943 is a deficient number, since it is larger than the sum of its proper divisors (1).

20101978943 is an equidigital number, since it uses as much as digits as its factorization.

20101978943 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108864, while the sum is 44.

The spelling of 20101978943 in words is "twenty billion, one hundred one million, nine hundred seventy-eight thousand, nine hundred forty-three".