21409655800 has 192 divisors, whose sum is σ = 56331394560. Its totient is φ = 7508160000.

The previous prime is 21409655783. The next prime is 21409655801. The reversal of 21409655800 is 855690412.

It is a super-2 number, since 2×21409655800² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21409655801) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 9028615 + ... + 9030985.

It is an arithmetic number, because the mean of its divisors is an integer number (293392680).

Almost surely, 2^21409655800 is an apocalyptic number.

21409655800 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 21409655800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28165697280).

21409655800 is an abundant number, since it is smaller than the sum of its proper divisors (34921738760).

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

21409655800 is a wasteful number, since it uses less digits than its factorization.

21409655800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2574 (or 2565 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 40.

The spelling of 21409655800 in words is "twenty-one billion, four hundred nine million, six hundred fifty-five thousand, eight hundred".