21021102010 has 16 divisors (see below), whose sum is σ = 39829456800. Its totient is φ = 7965891216.

The previous prime is 21021102001. The next prime is 21021102013. The reversal of 21021102010 is 1020112012.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is not an unprimeable number, because it can be changed into a prime (21021102013) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55318500 + ... + 55318879.

It is an arithmetic number, because the mean of its divisors is an integer number (2489341050).

Almost surely, 2^21021102010 is an apocalyptic number.

21021102010 is a deficient number, since it is larger than the sum of its proper divisors (18808354790).

21021102010 is a wasteful number, since it uses less digits than its factorization.

21021102010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110637405.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21021102010 its reverse (1020112012), we get a palindrome (22041214022).

The spelling of 21021102010 in words is "twenty-one billion, twenty-one million, one hundred two thousand, ten".