21771415771 has 16 divisors (see below), whose sum is σ = 24950750400. Its totient is φ = 18609429888.

The previous prime is 21771415769. The next prime is 21771415777. The reversal of 21771415771 is 17751417712.

It is not a de Polignac number, because 21771415771 - 2¹ = 21771415769 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21771415777) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8083101 + ... + 8085793.

It is an arithmetic number, because the mean of its divisors is an integer number (1559421900).

Almost surely, 2^21771415771 is an apocalyptic number.

21771415771 is a deficient number, since it is larger than the sum of its proper divisors (3179334629).

21771415771 is a wasteful number, since it uses less digits than its factorization.

21771415771 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5478.

The product of its digits is 96040, while the sum is 43.

The spelling of 21771415771 in words is "twenty-one billion, seven hundred seventy-one million, four hundred fifteen thousand, seven hundred seventy-one".