21315445532 has 12 divisors (see below), whose sum is σ = 37721154240. Its totient is φ = 10537972896.

The previous prime is 21315445471. The next prime is 21315445537. The reversal of 21315445532 is 23554451312.

It is a junction number, because it is equal to n+sod(n) for n = 21315445492 and 21315445501.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21315445537) 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, 29937068 + ... + 29937779.

It is an arithmetic number, because the mean of its divisors is an integer number (3143429520).

Almost surely, 2^21315445532 is an apocalyptic number.

It is an amenable number.

21315445532 is a deficient number, since it is larger than the sum of its proper divisors (16405708708).

21315445532 is a wasteful number, since it uses less digits than its factorization.

21315445532 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59874940 (or 59874938 counting only the distinct ones).

The product of its digits is 72000, while the sum is 35.

Adding to 21315445532 its reverse (23554451312), we get a palindrome (44869896844).

The spelling of 21315445532 in words is "twenty-one billion, three hundred fifteen million, four hundred forty-five thousand, five hundred thirty-two".