21503055030 has 128 divisors (see below), whose sum is σ = 56121569280. Its totient is φ = 5252782080.

The previous prime is 21503055011. The next prime is 21503055061. The reversal of 21503055030 is 3055030512.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2856832 + ... + 2864348.

It is an arithmetic number, because the mean of its divisors is an integer number (438449760).

Almost surely, 2^21503055030 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21503055030, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28060784640).

21503055030 is an abundant number, since it is smaller than the sum of its proper divisors (34618514250).

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

21503055030 is a wasteful number, since it uses less digits than its factorization.

21503055030 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7694.

The product of its (nonzero) digits is 2250, while the sum is 24.

Adding to 21503055030 its reverse (3055030512), we get a palindrome (24558085542).

The spelling of 21503055030 in words is "twenty-one billion, five hundred three million, fifty-five thousand, thirty".