21345326424 has 192 divisors, whose sum is σ = 60496619040. Its totient is φ = 6794311680.

The previous prime is 21345326417. The next prime is 21345326459. The reversal of 21345326424 is 42462354312.

21345326424 is a `hidden beast` number, since 2 + 1 + 3 + 4 + 5 + 3 + 2 + 642 + 4 = 666.

It is a super-2 number, since 2×21345326424² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 24906604 + ... + 24907460.

Almost surely, 2^21345326424 is an apocalyptic number.

21345326424 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21345326424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30248309520).

21345326424 is an abundant number, since it is smaller than the sum of its proper divisors (39151292616).

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

21345326424 is a wasteful number, since it uses less digits than its factorization.

21345326424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1090 (or 1083 counting only the distinct ones).

The product of its digits is 138240, while the sum is 36.

The spelling of 21345326424 in words is "twenty-one billion, three hundred forty-five million, three hundred twenty-six thousand, four hundred twenty-four".