21771346220 has 24 divisors (see below), whose sum is σ = 49236737424. Its totient is φ = 8038650816.

The previous prime is 21771346217. The next prime is 21771346229. The reversal of 21771346220 is 2264317712.

It is a super-2 number, since 2×21771346220² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21771346229) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41867714 + ... + 41868233.

It is an arithmetic number, because the mean of its divisors is an integer number (2051530726).

Almost surely, 2^21771346220 is an apocalyptic number.

21771346220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21771346220 is an abundant number, since it is smaller than the sum of its proper divisors (27465391204).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21771346220 is a wasteful number, since it uses less digits than its factorization.

21771346220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83735969 (or 83735967 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 35.

The spelling of 21771346220 in words is "twenty-one billion, seven hundred seventy-one million, three hundred forty-six thousand, two hundred twenty".