538357681 has 2 divisors, whose sum is σ = 538357682. Its totient is φ = 538357680.

The previous prime is 538357657. The next prime is 538357691. The reversal of 538357681 is 186753835.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 521711281 + 16646400 = 22841^2 + 4080^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-538357681 is a prime.

It is a super-2 number, since 2×538357681² = 579657985383395522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (538357691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 269178840 + 269178841.

It is an arithmetic number, because the mean of its divisors is an integer number (269178841).

Almost surely, 2^538357681 is an apocalyptic number.

It is an amenable number.

538357681 is a deficient number, since it is larger than the sum of its proper divisors (1).

538357681 is an equidigital number, since it uses as much as digits as its factorization.

538357681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 604800, while the sum is 46.

The square root of 538357681 is about 23202.5360898329. The cubic root of 538357681 is about 813.4989022684.

It can be divided in two parts, 53835 and 7681, that added together give a palindrome (61516).

The spelling of 538357681 in words is "five hundred thirty-eight million, three hundred fifty-seven thousand, six hundred eighty-one".