20378158477 has 2 divisors, whose sum is σ = 20378158478. Its totient is φ = 20378158476.

The previous prime is 20378158457. The next prime is 20378158487. The reversal of 20378158477 is 77485187302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20145260356 + 232898121 = 141934^2 + 15261^2 .

It is a cyclic number.

It is not a de Polignac number, because 20378158477 - 2¹¹ = 20378156429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20378158457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10189079238 + 10189079239.

It is an arithmetic number, because the mean of its divisors is an integer number (10189079239).

Almost surely, 2^20378158477 is an apocalyptic number.

It is an amenable number.

20378158477 is a deficient number, since it is larger than the sum of its proper divisors (1).

20378158477 is an equidigital number, since it uses as much as digits as its factorization.

20378158477 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2634240, while the sum is 52.

The spelling of 20378158477 in words is "twenty billion, three hundred seventy-eight million, one hundred fifty-eight thousand, four hundred seventy-seven".