21302155320 has 384 divisors, whose sum is σ = 71616960000. Its totient is φ = 5060435968.

The previous prime is 21302155307. The next prime is 21302155333. The reversal of 21302155320 is 2355120312.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21302155307) and next prime (21302155333).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 59337301 + ... + 59337659.

It is an arithmetic number, because the mean of its divisors is an integer number (186502500).

Almost surely, 2^21302155320 is an apocalyptic number.

21302155320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21302155320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35808480000).

21302155320 is an abundant number, since it is smaller than the sum of its proper divisors (50314804680).

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

21302155320 is a wasteful number, since it uses less digits than its factorization.

21302155320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 495 (or 474 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 24.

Adding to 21302155320 its reverse (2355120312), we get a palindrome (23657275632).

The spelling of 21302155320 in words is "twenty-one billion, three hundred two million, one hundred fifty-five thousand, three hundred twenty".