20702847662881 has 2 divisors, whose sum is σ = 20702847662882. Its totient is φ = 20702847662880.

The previous prime is 20702847662843. The next prime is 20702847662911. The reversal of 20702847662881 is 18826674820702.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20701635509025 + 1212153856 = 4549905^2 + 34816^2 .

It is a cyclic number.

It is not a de Polignac number, because 20702847662881 - 2¹⁹ = 20702847138593 is a prime.

It is a super-2 number, since 2×20702847662881² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20702847662281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10351423831440 + 10351423831441.

It is an arithmetic number, because the mean of its divisors is an integer number (10351423831441).

Almost surely, 2^{20702847662881} is an apocalyptic number.

It is an amenable number.

20702847662881 is a deficient number, since it is larger than the sum of its proper divisors (1).

20702847662881 is an equidigital number, since it uses as much as digits as its factorization.

20702847662881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 28901376, while the sum is 61.

The spelling of 20702847662881 in words is "twenty trillion, seven hundred two billion, eight hundred forty-seven million, six hundred sixty-two thousand, eight hundred eighty-one".