21311000100 has 144 divisors (see below), whose sum is σ = 73781111040. Its totient is φ = 5245776000.

The previous prime is 21311000089. The next prime is 21311000107. The reversal of 21311000100 is 100011312.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (21311000107) 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, 268476 + ... + 338675.

Almost surely, 2^21311000100 is an apocalyptic number.

21311000100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21311000100 is an abundant number, since it is smaller than the sum of its proper divisors (52470110940).

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

21311000100 is a wasteful number, since it uses less digits than its factorization.

21311000100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 607187 (or 607174 counting only the distinct ones).

The product of its (nonzero) digits is 6, while the sum is 9.

Adding to 21311000100 its reverse (100011312), we get a palindrome (21411011412).

The spelling of 21311000100 in words is "twenty-one billion, three hundred eleven million, one hundred", and thus it is an aban number.