21402177712843 has 2 divisors, whose sum is σ = 21402177712844. Its totient is φ = 21402177712842.

The previous prime is 21402177712823. The next prime is 21402177712849. The reversal of 21402177712843 is 34821777120412.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21402177712843 is a prime.

It is a super-2 number, since 2×21402177712843² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21402177712849) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10701088856421 + 10701088856422.

It is an arithmetic number, because the mean of its divisors is an integer number (10701088856422).

Almost surely, 2^{21402177712843} is an apocalyptic number.

21402177712843 is a deficient number, since it is larger than the sum of its proper divisors (1).

21402177712843 is an equidigital number, since it uses as much as digits as its factorization.

21402177712843 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1053696, while the sum is 49.

The spelling of 21402177712843 in words is "twenty-one trillion, four hundred two billion, one hundred seventy-seven million, seven hundred twelve thousand, eight hundred forty-three".