21021300120 has 64 divisors (see below), whose sum is σ = 63131257440. Its totient is φ = 5599692800.

The previous prime is 21021300119. The next prime is 21021300121. The reversal of 21021300120 is 2100312012.

It is an interprime number because it is at equal distance from previous prime (21021300119) and next prime (21021300121).

It is a super-2 number, since 2×21021300120² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 21021300096 and 21021300105.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021300121) 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, 19840 + ... + 206000.

Almost surely, 2^21021300120 is an apocalyptic number.

21021300120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21021300120 is an abundant number, since it is smaller than the sum of its proper divisors (42109957320).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21021300120 is a wasteful number, since it uses less digits than its factorization.

21021300120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187116 (or 187112 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

Adding to 21021300120 its reverse (2100312012), we get a palindrome (23121612132).

The spelling of 21021300120 in words is "twenty-one billion, twenty-one million, three hundred thousand, one hundred twenty".