264817206781 has 2 divisors, whose sum is σ = 264817206782. Its totient is φ = 264817206780.

The previous prime is 264817206749. The next prime is 264817206791. The reversal of 264817206781 is 187602718462.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 250955912025 + 13861294756 = 500955^2 + 117734^2 .

It is a cyclic number.

It is not a de Polignac number, because 264817206781 - 2⁵ = 264817206749 is a prime.

It is a super-2 number, since 2×264817206781² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (264817206721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 132408603390 + 132408603391.

It is an arithmetic number, because the mean of its divisors is an integer number (132408603391).

Almost surely, 2^264817206781 is an apocalyptic number.

It is an amenable number.

264817206781 is a deficient number, since it is larger than the sum of its proper divisors (1).

264817206781 is an equidigital number, since it uses as much as digits as its factorization.

264817206781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1806336, while the sum is 52.

The spelling of 264817206781 in words is "two hundred sixty-four billion, eight hundred seventeen million, two hundred six thousand, seven hundred eighty-one".