21028473620 has 192 divisors, whose sum is σ = 57131827200. Its totient is φ = 6308682240.

The previous prime is 21028473619. The next prime is 21028473623. The reversal of 21028473620 is 2637482012.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21028473623) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 21391649 + ... + 21392631.

It is an arithmetic number, because the mean of its divisors is an integer number (297561600).

Almost surely, 2^21028473620 is an apocalyptic number.

21028473620 is a gapful number since it is divisible by the number (20) 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 21028473620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28565913600).

21028473620 is an abundant number, since it is smaller than the sum of its proper divisors (36103353580).

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

21028473620 is a wasteful number, since it uses less digits than its factorization.

21028473620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1518 (or 1516 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 35.

The spelling of 21028473620 in words is "twenty-one billion, twenty-eight million, four hundred seventy-three thousand, six hundred twenty".