21741658871 has 2 divisors, whose sum is σ = 21741658872. Its totient is φ = 21741658870.

The previous prime is 21741658859. The next prime is 21741658879. The reversal of 21741658871 is 17885614712.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21741658871 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21741658879) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10870829435 + 10870829436.

It is an arithmetic number, because the mean of its divisors is an integer number (10870829436).

Almost surely, 2^21741658871 is an apocalyptic number.

21741658871 is a deficient number, since it is larger than the sum of its proper divisors (1).

21741658871 is an equidigital number, since it uses as much as digits as its factorization.

21741658871 is an evil number, because the sum of its binary digits is even.

The product of its digits is 752640, while the sum is 50.

The spelling of 21741658871 in words is "twenty-one billion, seven hundred forty-one million, six hundred fifty-eight thousand, eight hundred seventy-one".