21012215024 has 20 divisors (see below), whose sum is σ = 41031730944. Its totient is φ = 10423381248.

The previous prime is 21012215023. The next prime is 21012215047. The reversal of 21012215024 is 42051221012.

It is a super-2 number, since 2×21012215024² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21012214987 and 21012215005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012215023) 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, 5168297 + ... + 5172360.

Almost surely, 2^21012215024 is an apocalyptic number.

It is an amenable number.

21012215024 is a deficient number, since it is larger than the sum of its proper divisors (20019515920).

21012215024 is a wasteful number, since it uses less digits than its factorization.

21012215024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10340792 (or 10340786 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 20.

Adding to 21012215024 its reverse (42051221012), we get a palindrome (63063436036).

The spelling of 21012215024 in words is "twenty-one billion, twelve million, two hundred fifteen thousand, twenty-four".