215276563781 has 2 divisors, whose sum is σ = 215276563782. Its totient is φ = 215276563780.

The previous prime is 215276563771. The next prime is 215276563793. The reversal of 215276563781 is 187365672512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 213934000900 + 1342562881 = 462530^2 + 36641^2 .

It is a cyclic number.

It is not a de Polignac number, because 215276563781 - 2⁶ = 215276563717 is a prime.

It is a super-2 number, since 2×215276563781² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215276563741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107638281890 + 107638281891.

It is an arithmetic number, because the mean of its divisors is an integer number (107638281891).

Almost surely, 2^215276563781 is an apocalyptic number.

It is an amenable number.

215276563781 is a deficient number, since it is larger than the sum of its proper divisors (1).

215276563781 is an equidigital number, since it uses as much as digits as its factorization.

215276563781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4233600, while the sum is 53.

The spelling of 215276563781 in words is "two hundred fifteen billion, two hundred seventy-six million, five hundred sixty-three thousand, seven hundred eighty-one".