264634781 has 2 divisors, whose sum is σ = 264634782. Its totient is φ = 264634780.

The previous prime is 264634739. The next prime is 264634807. The reversal of 264634781 is 187436462.

264634781 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 263542756 + 1092025 = 16234^2 + 1045^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-264634781 is a prime.

It is a super-2 number, since 2×264634781² = 140063134629835922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (264634081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 132317390 + 132317391.

It is an arithmetic number, because the mean of its divisors is an integer number (132317391).

Almost surely, 2^264634781 is an apocalyptic number.

It is an amenable number.

264634781 is a deficient number, since it is larger than the sum of its proper divisors (1).

264634781 is an equidigital number, since it uses as much as digits as its factorization.

264634781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 193536, while the sum is 41.

The square root of 264634781 is about 16267.5991160343. The cubic root of 264634781 is about 642.0206165356.

The spelling of 264634781 in words is "two hundred sixty-four million, six hundred thirty-four thousand, seven hundred eighty-one".