21321320010 has 32 divisors (see below), whose sum is σ = 51413700672. Its totient is φ = 5658737280.

The previous prime is 21321319979. The next prime is 21321320023. The reversal of 21321320010 is 1002312312.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1677819 + ... + 1690478.

It is an arithmetic number, because the mean of its divisors is an integer number (1606678146).

Almost surely, 2^21321320010 is an apocalyptic number.

21321320010 is an abundant number, since it is smaller than the sum of its proper divisors (30092380662).

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

21321320010 is a wasteful number, since it uses less digits than its factorization.

21321320010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3368518.

The product of its (nonzero) digits is 72, while the sum is 15.

Adding to 21321320010 its reverse (1002312312), we get a palindrome (22323632322).

The spelling of 21321320010 in words is "twenty-one billion, three hundred twenty-one million, three hundred twenty thousand, ten".