21220062646542 has 16 divisors (see below), whose sum is σ = 42440294096640. Its totient is φ = 7073326081592.

The previous prime is 21220062646483. The next prime is 21220062646543. The reversal of 21220062646542 is 24564626002212.

It is a junction number, because it is equal to n+sod(n) for n = 21220062646494 and 21220062646503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220062646543) 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, 5368968 + ... + 8441915.

It is an arithmetic number, because the mean of its divisors is an integer number (2652518381040).

Almost surely, 2^{21220062646542} is an apocalyptic number.

21220062646542 is an abundant number, since it is smaller than the sum of its proper divisors (21220231450098).

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

21220062646542 is a wasteful number, since it uses less digits than its factorization.

21220062646542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14066967.

The product of its (nonzero) digits is 552960, while the sum is 42.

Adding to 21220062646542 its reverse (24564626002212), we get a palindrome (45784688648754).

The spelling of 21220062646542 in words is "twenty-one trillion, two hundred twenty billion, sixty-two million, six hundred forty-six thousand, five hundred forty-two".