21121022000 has 80 divisors (see below), whose sum is σ = 54999208992. Its totient is φ = 7798521600.

The previous prime is 21121021991. The next prime is 21121022017. The reversal of 21121022000 is 22012112.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

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, 380174 + ... + 432173.

Almost surely, 2^21121022000 is an apocalyptic number.

21121022000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21121022000 is an abundant number, since it is smaller than the sum of its proper divisors (33878186992).

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

21121022000 is a wasteful number, since it uses less digits than its factorization.

21121022000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 812383 (or 812367 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21121022000 its reverse (22012112), we get a palindrome (21143034112).

The spelling of 21121022000 in words is "twenty-one billion, one hundred twenty-one million, twenty-two thousand".