21420543356 has 12 divisors (see below), whose sum is σ = 39115774992. Its totient is φ = 10244607648.

The previous prime is 21420543349. The next prime is 21420543359. The reversal of 21420543356 is 65334502412.

It is a super-3 number, since 3×21420543356³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21420543359) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 116415905 + ... + 116416088.

It is an arithmetic number, because the mean of its divisors is an integer number (3259647916).

Almost surely, 2^21420543356 is an apocalyptic number.

It is an amenable number.

21420543356 is a deficient number, since it is larger than the sum of its proper divisors (17695231636).

21420543356 is a wasteful number, since it uses less digits than its factorization.

21420543356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 232832020 (or 232832018 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 35.

The spelling of 21420543356 in words is "twenty-one billion, four hundred twenty million, five hundred forty-three thousand, three hundred fifty-six".