21231123000 has 64 divisors (see below), whose sum is σ = 66241113120. Its totient is φ = 5661632000.

The previous prime is 21231122993. The next prime is 21231123079. The reversal of 21231123000 is 32113212.

It is a super-2 number, since 2×21231123000² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

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, 3535521 + ... + 3541520.

Almost surely, 2^21231123000 is an apocalyptic number.

21231123000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21231123000 is an abundant number, since it is smaller than the sum of its proper divisors (45009990120).

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

21231123000 is a wasteful number, since it uses less digits than its factorization.

21231123000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7077065 (or 7077051 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

Adding to 21231123000 its reverse (32113212), we get a palindrome (21263236212).

The spelling of 21231123000 in words is "twenty-one billion, two hundred thirty-one million, one hundred twenty-three thousand".