21240216234 has 12 divisors (see below), whose sum is σ = 46020468546. Its totient is φ = 7080072072.

The previous prime is 21240216199. The next prime is 21240216247. The reversal of 21240216234 is 43261204212.

21240216234 is a `hidden beast` number, since 2 + 12 + 4 + 0 + 21 + 623 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 20671250625 + 568965609 = 143775^2 + 23853^2 .

It is a super-2 number, since 2×21240216234² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21240216198 and 21240216207.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 590005989 + ... + 590006024.

Almost surely, 2^21240216234 is an apocalyptic number.

21240216234 is an abundant number, since it is smaller than the sum of its proper divisors (24780252312).

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

21240216234 is a wasteful number, since it uses less digits than its factorization.

21240216234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1180012021 (or 1180012018 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

The spelling of 21240216234 in words is "twenty-one billion, two hundred forty million, two hundred sixteen thousand, two hundred thirty-four".