23021355520 has 40 divisors (see below), whose sum is σ = 55197303084. Its totient is φ = 9208541184.

The previous prime is 23021355499. The next prime is 23021355541. The reversal of 23021355520 is 2555312032.

It is an interprime number because it is at equal distance from previous prime (23021355499) and next prime (23021355541).

It can be written as a sum of positive squares in 2 ways, for example, as 22750292224 + 271063296 = 150832^2 + 16464^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4493799 + ... + 4498918.

Almost surely, 2^23021355520 is an apocalyptic number.

23021355520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23021355520 is an abundant number, since it is smaller than the sum of its proper divisors (32175947564).

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

23021355520 is an frugal number, since it uses more digits than its factorization.

23021355520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8992740 (or 8992724 counting only the distinct ones).

The product of its (nonzero) digits is 9000, while the sum is 28.

Adding to 23021355520 its reverse (2555312032), we get a palindrome (25576667552).

The spelling of 23021355520 in words is "twenty-three billion, twenty-one million, three hundred fifty-five thousand, five hundred twenty".