42912526781 has 2 divisors, whose sum is σ = 42912526782. Its totient is φ = 42912526780.

The previous prime is 42912526721. The next prime is 42912526807. The reversal of 42912526781 is 18762521924.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42664968025 + 247558756 = 206555^2 + 15734^2 .

It is a cyclic number.

It is not a de Polignac number, because 42912526781 - 2⁶ = 42912526717 is a prime.

It is a super-2 number, since 2×42912526781² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42912526721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21456263390 + 21456263391.

It is an arithmetic number, because the mean of its divisors is an integer number (21456263391).

Almost surely, 2^42912526781 is an apocalyptic number.

It is an amenable number.

42912526781 is a deficient number, since it is larger than the sum of its proper divisors (1).

42912526781 is an equidigital number, since it uses as much as digits as its factorization.

42912526781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 483840, while the sum is 47.

The spelling of 42912526781 in words is "forty-two billion, nine hundred twelve million, five hundred twenty-six thousand, seven hundred eighty-one".