21033515424 has 24 divisors (see below), whose sum is σ = 55212978240. Its totient is φ = 7011171776.

The previous prime is 21033515401. The next prime is 21033515429. The reversal of 21033515424 is 42451533012.

It is a tau number, because it is divible by the number of its divisors (24).

It is a junction number, because it is equal to n+sod(n) for n = 21033515391 and 21033515400.

It is not an unprimeable number, because it can be changed into a prime (21033515429) 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, 109549464 + ... + 109549655.

It is an arithmetic number, because the mean of its divisors is an integer number (2300540760).

Almost surely, 2^21033515424 is an apocalyptic number.

21033515424 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21033515424 is an abundant number, since it is smaller than the sum of its proper divisors (34179462816).

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

21033515424 is a wasteful number, since it uses less digits than its factorization.

21033515424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 219099132 (or 219099124 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 30.

The spelling of 21033515424 in words is "twenty-one billion, thirty-three million, five hundred fifteen thousand, four hundred twenty-four".