21213012000 has 96 divisors (see below), whose sum is σ = 69493866624. Its totient is φ = 5656800000.

The previous prime is 21213011999. The next prime is 21213012011. The reversal of 21213012000 is 21031212.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×21213012000² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 871876 + ... + 895875.

It is an arithmetic number, because the mean of its divisors is an integer number (723894444).

Almost surely, 2^21213012000 is an apocalyptic number.

21213012000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21213012000 is an abundant number, since it is smaller than the sum of its proper divisors (48280854624).

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

21213012000 is a wasteful number, since it uses less digits than its factorization.

21213012000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1767779 (or 1767761 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

Adding to 21213012000 its reverse (21031212), we get a palindrome (21234043212).

The spelling of 21213012000 in words is "twenty-one billion, two hundred thirteen million, twelve thousand".