21003831264 has 288 divisors, whose sum is σ = 62386837632. Its totient is φ = 6149606400.

The previous prime is 21003831253. The next prime is 21003831281. The reversal of 21003831264 is 46213830012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 99544119 + ... + 99544329.

It is an arithmetic number, because the mean of its divisors is an integer number (216620964).

Almost surely, 2^21003831264 is an apocalyptic number.

21003831264 is a gapful number since it is divisible by the number (24) 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 21003831264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31193418816).

21003831264 is an abundant number, since it is smaller than the sum of its proper divisors (41383006368).

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

21003831264 is a wasteful number, since it uses less digits than its factorization.

21003831264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 382 (or 343 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The spelling of 21003831264 in words is "twenty-one billion, three million, eight hundred thirty-one thousand, two hundred sixty-four".