21403021120 has 56 divisors (see below), whose sum is σ = 54886411944. Its totient is φ = 7902652416.

The previous prime is 21403021117. The next prime is 21403021169. The reversal of 21403021120 is 2112030412.

It can be written as a sum of positive squares in 4 ways, for example, as 4469724736 + 16933296384 = 66856^2 + 130128^2 .

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 21403021094 and 21403021103.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2568319 + ... + 2576638.

It is an arithmetic number, because the mean of its divisors is an integer number (980114499).

Almost surely, 2^21403021120 is an apocalyptic number.

21403021120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21403021120 is an abundant number, since it is smaller than the sum of its proper divisors (33483390824).

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

21403021120 is a wasteful number, since it uses less digits than its factorization.

21403021120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5144987 (or 5144977 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 21403021120 its reverse (2112030412), we get a palindrome (23515051532).

The spelling of 21403021120 in words is "twenty-one billion, four hundred three million, twenty-one thousand, one hundred twenty".