21503112000 has 224 divisors, whose sum is σ = 71808197760. Its totient is φ = 5669171200.

The previous prime is 21503111977. The next prime is 21503112023. The reversal of 21503112000 is 21130512.

It is an interprime number because it is at equal distance from previous prime (21503111977) and next prime (21503112023).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2130967 + ... + 2141033.

Almost surely, 2^21503112000 is an apocalyptic number.

21503112000 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 21503112000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35904098880).

21503112000 is an abundant number, since it is smaller than the sum of its proper divisors (50305085760).

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

21503112000 is a wasteful number, since it uses less digits than its factorization.

21503112000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10186 (or 10166 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 15.

Adding to 21503112000 its reverse (21130512), we get a palindrome (21524242512).

The spelling of 21503112000 in words is "twenty-one billion, five hundred three million, one hundred twelve thousand".