21023053040 has 120 divisors (see below), whose sum is σ = 54260527104. Its totient is φ = 7568704000.

The previous prime is 21023053039. The next prime is 21023053049. The reversal of 21023053040 is 4035032012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21023053049) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 966929 + ... + 988431.

Almost surely, 2^21023053040 is an apocalyptic number.

21023053040 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 21023053040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27130263552).

21023053040 is an abundant number, since it is smaller than the sum of its proper divisors (33237474064).

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

21023053040 is a wasteful number, since it uses less digits than its factorization.

21023053040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21639 (or 21622 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 20.

Adding to 21023053040 its reverse (4035032012), we get a palindrome (25058085052).

The spelling of 21023053040 in words is "twenty-one billion, twenty-three million, fifty-three thousand, forty".