20146991077 has 2 divisors, whose sum is σ = 20146991078. Its totient is φ = 20146991076.

The previous prime is 20146991063. The next prime is 20146991089. The reversal of 20146991077 is 77019964102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15048174241 + 5098816836 = 122671^2 + 71406^2 .

It is a cyclic number.

It is not a de Polignac number, because 20146991077 - 2¹⁹ = 20146466789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20146997077) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10073495538 + 10073495539.

It is an arithmetic number, because the mean of its divisors is an integer number (10073495539).

Almost surely, 2^20146991077 is an apocalyptic number.

It is an amenable number.

20146991077 is a deficient number, since it is larger than the sum of its proper divisors (1).

20146991077 is an equidigital number, since it uses as much as digits as its factorization.

20146991077 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 190512, while the sum is 46.

The spelling of 20146991077 in words is "twenty billion, one hundred forty-six million, nine hundred ninety-one thousand, seventy-seven".