21435543100 has 144 divisors (see below), whose sum is σ = 50171226336. Its totient is φ = 7920640000.

The previous prime is 21435543091. The next prime is 21435543113. The reversal of 21435543100 is 134553412.

It is a super-2 number, since 2×21435543100² (a number of 21 digits) contains 22 as substring.

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, 22492224 + ... + 22493176.

It is an arithmetic number, because the mean of its divisors is an integer number (348411294).

Almost surely, 2^21435543100 is an apocalyptic number.

21435543100 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 21435543100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25085613168).

21435543100 is an abundant number, since it is smaller than the sum of its proper divisors (28735683236).

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

21435543100 is a wasteful number, since it uses less digits than its factorization.

21435543100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1216 (or 1209 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 28.

The spelling of 21435543100 in words is "twenty-one billion, four hundred thirty-five million, five hundred forty-three thousand, one hundred".