21781784130522 has 32 divisors (see below), whose sum is σ = 47006782220160. Its totient is φ = 6688920246720.

The previous prime is 21781784130517. The next prime is 21781784130553. The reversal of 21781784130522 is 22503148718712.

It is a happy number.

It is a super-2 number, since 2×21781784130522² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 274276254 + ... + 274355657.

It is an arithmetic number, because the mean of its divisors is an integer number (1468961944380).

Almost surely, 2^{21781784130522} is an apocalyptic number.

21781784130522 is an abundant number, since it is smaller than the sum of its proper divisors (25224998089638).

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

21781784130522 is a wasteful number, since it uses less digits than its factorization.

21781784130522 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 548632438.

The product of its (nonzero) digits is 1505280, while the sum is 51.

The spelling of 21781784130522 in words is "twenty-one trillion, seven hundred eighty-one billion, seven hundred eighty-four million, one hundred thirty thousand, five hundred twenty-two".