21031220102 has 32 divisors (see below), whose sum is σ = 33645507840. Its totient is φ = 9838655200.

The previous prime is 21031220083. The next prime is 21031220107. The reversal of 21031220102 is 20102213012.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21031220107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 358349 + ... + 412887.

It is an arithmetic number, because the mean of its divisors is an integer number (1051422120).

Almost surely, 2^21031220102 is an apocalyptic number.

21031220102 is a deficient number, since it is larger than the sum of its proper divisors (12614287738).

21031220102 is a wasteful number, since it uses less digits than its factorization.

21031220102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54748.

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 21031220102 its reverse (20102213012), we get a palindrome (41133433114).

The spelling of 21031220102 in words is "twenty-one billion, thirty-one million, two hundred twenty thousand, one hundred two".