20158746961 has 2 divisors, whose sum is σ = 20158746962. Its totient is φ = 20158746960.

The previous prime is 20158746917. The next prime is 20158747009. The reversal of 20158746961 is 16964785102.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18572238400 + 1586508561 = 136280^2 + 39831^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20158746961 is a prime.

It is not a weakly prime, because it can be changed into another prime (20158746161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10079373480 + 10079373481.

It is an arithmetic number, because the mean of its divisors is an integer number (10079373481).

Almost surely, 2^20158746961 is an apocalyptic number.

It is an amenable number.

20158746961 is a deficient number, since it is larger than the sum of its proper divisors (1).

20158746961 is an equidigital number, since it uses as much as digits as its factorization.

20158746961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 725760, while the sum is 49.

The spelling of 20158746961 in words is "twenty billion, one hundred fifty-eight million, seven hundred forty-six thousand, nine hundred sixty-one".