21000421010 has 8 divisors (see below), whose sum is σ = 37800757836. Its totient is φ = 8400168400.

The previous prime is 21000421003. The next prime is 21000421033. The reversal of 21000421010 is 1012400012.

It can be written as a sum of positive squares in 2 ways, for example, as 17548035961 + 3452385049 = 132469^2 + 58757^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 21000420982 and 21000421000.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1050021041 + ... + 1050021060.

Almost surely, 2^21000421010 is an apocalyptic number.

21000421010 is a deficient number, since it is larger than the sum of its proper divisors (16800336826).

21000421010 is a wasteful number, since it uses less digits than its factorization.

21000421010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2100042108.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21000421010 its reverse (1012400012), we get a palindrome (22012821022).

The spelling of 21000421010 in words is "twenty-one billion, four hundred twenty-one thousand, ten".