21101221010 has 16 divisors (see below), whose sum is σ = 38865505536. Its totient is φ = 8244197808.

The previous prime is 21101220991. The next prime is 21101221021. The reversal of 21101221010 is 1012210112.

It is a super-2 number, since 2×21101221010² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21101220982 and 21101221000.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24535874 + ... + 24536733.

It is an arithmetic number, because the mean of its divisors is an integer number (2429094096).

Almost surely, 2^21101221010 is an apocalyptic number.

21101221010 is a deficient number, since it is larger than the sum of its proper divisors (17764284526).

21101221010 is a wasteful number, since it uses less digits than its factorization.

21101221010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49072657.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21101221010 its reverse (1012210112), we get a palindrome (22113431122).

The spelling of 21101221010 in words is "twenty-one billion, one hundred one million, two hundred twenty-one thousand, ten".