21010403020 has 96 divisors (see below), whose sum is σ = 47497798656. Its totient is φ = 7778304000.

The previous prime is 21010403017. The next prime is 21010403023. The reversal of 21010403020 is 2030401012.

It is an interprime number because it is at equal distance from previous prime (21010403017) and next prime (21010403023).

It is not an unprimeable number, because it can be changed into a prime (21010403023) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9951765 + ... + 9953875.

It is an arithmetic number, because the mean of its divisors is an integer number (494768736).

Almost surely, 2^21010403020 is an apocalyptic number.

21010403020 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 21010403020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23748899328).

21010403020 is an abundant number, since it is smaller than the sum of its proper divisors (26487395636).

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

21010403020 is a wasteful number, since it uses less digits than its factorization.

21010403020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2611 (or 2609 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

Adding to 21010403020 its reverse (2030401012), we get a palindrome (23040804032).

The spelling of 21010403020 in words is "twenty-one billion, ten million, four hundred three thousand, twenty".