21499231600 has 720 divisors, whose sum is σ = 70675476480. Its totient is φ = 6133248000.

The previous prime is 21499231597. The next prime is 21499231603. The reversal of 21499231600 is 613299412.

It is an interprime number because it is at equal distance from previous prime (21499231597) and next prime (21499231603).

It is a self number, because there is not a number n which added to its sum of digits gives 21499231600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21499231603) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 241564356 + ... + 241564444.

It is an arithmetic number, because the mean of its divisors is an integer number (98160384).

Almost surely, 2^21499231600 is an apocalyptic number.

21499231600 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 21499231600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35337738240).

21499231600 is an abundant number, since it is smaller than the sum of its proper divisors (49176244880).

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

21499231600 is a wasteful number, since it uses less digits than its factorization.

21499231600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 190 (or 168 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 37.

The spelling of 21499231600 in words is "twenty-one billion, four hundred ninety-nine million, two hundred thirty-one thousand, six hundred".