21020012210 has 48 divisors (see below), whose sum is σ = 39617323776. Its totient is φ = 8021580000.

The previous prime is 21020012207. The next prime is 21020012231. The reversal of 21020012210 is 1221002012.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21020012191 and 21020012200.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1555985 + ... + 1569435.

It is an arithmetic number, because the mean of its divisors is an integer number (825360912).

Almost surely, 2^21020012210 is an apocalyptic number.

21020012210 is a deficient number, since it is larger than the sum of its proper divisors (18597311566).

21020012210 is a wasteful number, since it uses less digits than its factorization.

21020012210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13631 (or 13560 counting only the distinct ones).

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

Adding to 21020012210 its reverse (1221002012), we get a palindrome (22241014222).

The spelling of 21020012210 in words is "twenty-one billion, twenty million, twelve thousand, two hundred ten".