19512946081 has 2 divisors, whose sum is σ = 19512946082. Its totient is φ = 19512946080.

The previous prime is 19512946051. The next prime is 19512946087. The reversal of 19512946081 is 18064921591.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16527416481 + 2985529600 = 128559^2 + 54640^2 .

It is a cyclic number.

It is not a de Polignac number, because 19512946081 - 2²³ = 19504557473 is a prime.

It is a super-2 number, since 2×19512946081² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (19512946087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9756473040 + 9756473041.

It is an arithmetic number, because the mean of its divisors is an integer number (9756473041).

Almost surely, 2^19512946081 is an apocalyptic number.

It is an amenable number.

19512946081 is a deficient number, since it is larger than the sum of its proper divisors (1).

19512946081 is an equidigital number, since it uses as much as digits as its factorization.

19512946081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 155520, while the sum is 46.

The spelling of 19512946081 in words is "nineteen billion, five hundred twelve million, nine hundred forty-six thousand, eighty-one".