21098649600 has 864 divisors, whose sum is σ = 89564267520. Its totient is φ = 4644864000.

The previous prime is 21098649577. The next prime is 21098649613. The reversal of 21098649600 is 694689012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 99993495 + ... + 99993705.

Almost surely, 2^21098649600 is an apocalyptic number.

21098649600 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 21098649600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44782133760).

21098649600 is an abundant number, since it is smaller than the sum of its proper divisors (68465617920).

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

21098649600 is a wasteful number, since it uses less digits than its factorization.

21098649600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 287 (or 259 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The spelling of 21098649600 in words is "twenty-one billion, ninety-eight million, six hundred forty-nine thousand, six hundred".