21820216024 has 16 divisors (see below), whose sum is σ = 40914478800. Its totient is φ = 10909688352.

The previous prime is 21820216009. The next prime is 21820216039. The reversal of 21820216024 is 42061202812.

It is an interprime number because it is at equal distance from previous prime (21820216009) and next prime (21820216039).

It is a super-2 number, since 2×21820216024² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21820215983 and 21820216001.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 351522 + ... + 408910.

It is an arithmetic number, because the mean of its divisors is an integer number (2557154925).

Almost surely, 2^21820216024 is an apocalyptic number.

It is an amenable number.

21820216024 is a deficient number, since it is larger than the sum of its proper divisors (19094262776).

21820216024 is a wasteful number, since it uses less digits than its factorization.

21820216024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104922 (or 104918 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 28.

Adding to 21820216024 its reverse (42061202812), we get a palindrome (63881418836).

The spelling of 21820216024 in words is "twenty-one billion, eight hundred twenty million, two hundred sixteen thousand, twenty-four".