21240312004 has 24 divisors (see below), whose sum is σ = 38496100608. Its totient is φ = 10247791680.

The previous prime is 21240311987. The next prime is 21240312029. The reversal of 21240312004 is 40021304212.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 782289 + ... + 808984.

It is an arithmetic number, because the mean of its divisors is an integer number (1604004192).

Almost surely, 2^21240312004 is an apocalyptic number.

It is an amenable number.

21240312004 is a deficient number, since it is larger than the sum of its proper divisors (17255788604).

21240312004 is a wasteful number, since it uses less digits than its factorization.

21240312004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1591395 (or 1591393 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 21240312004 its reverse (40021304212), we get a palindrome (61261616216).

The spelling of 21240312004 in words is "twenty-one billion, two hundred forty million, three hundred twelve thousand, four".