21123033320 has 16 divisors (see below), whose sum is σ = 47526825060. Its totient is φ = 8449213312.

The previous prime is 21123033313. The next prime is 21123033359. The reversal of 21123033320 is 2333032112.

It can be written as a sum of positive squares in 2 ways, for example, as 20220271204 + 902762116 = 142198^2 + 30046^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 21123033292 and 21123033301.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 264037877 + ... + 264037956.

Almost surely, 2^21123033320 is an apocalyptic number.

21123033320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21123033320 is an abundant number, since it is smaller than the sum of its proper divisors (26403791740).

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

21123033320 is a wasteful number, since it uses less digits than its factorization.

21123033320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 528075844 (or 528075840 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 20.

Adding to 21123033320 its reverse (2333032112), we get a palindrome (23456065432).

The spelling of 21123033320 in words is "twenty-one billion, one hundred twenty-three million, thirty-three thousand, three hundred twenty".