21234177571 has 2 divisors, whose sum is σ = 21234177572. Its totient is φ = 21234177570.

The previous prime is 21234177511. The next prime is 21234177581. The reversal of 21234177571 is 17577143212.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21234177571 - 2⁷ = 21234177443 is a prime.

It is not a weakly prime, because it can be changed into another prime (21234177511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10617088785 + 10617088786.

It is an arithmetic number, because the mean of its divisors is an integer number (10617088786).

Almost surely, 2^21234177571 is an apocalyptic number.

21234177571 is a deficient number, since it is larger than the sum of its proper divisors (1).

21234177571 is an equidigital number, since it uses as much as digits as its factorization.

21234177571 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 82320, while the sum is 40.

The spelling of 21234177571 in words is "twenty-one billion, two hundred thirty-four million, one hundred seventy-seven thousand, five hundred seventy-one".