21020495328 has 288 divisors, whose sum is σ = 72582531840. Its totient is φ = 5858749440.

The previous prime is 21020495311. The next prime is 21020495333. The reversal of 21020495328 is 82359402012.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-2 number, since 2×21020495328² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 21020495292 and 21020495301.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2227003 + ... + 2236421.

It is an arithmetic number, because the mean of its divisors is an integer number (252022680).

Almost surely, 2^21020495328 is an apocalyptic number.

21020495328 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21020495328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36291265920).

21020495328 is an abundant number, since it is smaller than the sum of its proper divisors (51562036512).

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

21020495328 is an equidigital number, since it uses as much as digits as its factorization.

21020495328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9492 (or 9472 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The spelling of 21020495328 in words is "twenty-one billion, twenty million, four hundred ninety-five thousand, three hundred twenty-eight".