21503133066 has 32 divisors (see below), whose sum is σ = 44018124480. Its totient is φ = 6999156864.

The previous prime is 21503133031. The next prime is 21503133073. The reversal of 21503133066 is 66033130512.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1227900 + ... + 1245288.

It is an arithmetic number, because the mean of its divisors is an integer number (1375566390).

Almost surely, 2^21503133066 is an apocalyptic number.

21503133066 is an abundant number, since it is smaller than the sum of its proper divisors (22514991414).

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

21503133066 is a wasteful number, since it uses less digits than its factorization.

21503133066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22230.

The product of its (nonzero) digits is 9720, while the sum is 30.

Adding to 21503133066 its reverse (66033130512), we get a palindrome (87536263578).

The spelling of 21503133066 in words is "twenty-one billion, five hundred three million, one hundred thirty-three thousand, sixty-six".