21230221452 has 48 divisors (see below), whose sum is σ = 57219426432. Its totient is φ = 6054964480.

The previous prime is 21230221447. The next prime is 21230221457. The reversal of 21230221452 is 25412203212.

It is an interprime number because it is at equal distance from previous prime (21230221447) and next prime (21230221457).

It is not an unprimeable number, because it can be changed into a prime (21230221457) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4728198 + ... + 4732685.

It is an arithmetic number, because the mean of its divisors is an integer number (1192071384).

Almost surely, 2^21230221452 is an apocalyptic number.

21230221452 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21230221452 is an abundant number, since it is smaller than the sum of its proper divisors (35989204980).

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

21230221452 is a wasteful number, since it uses less digits than its factorization.

21230221452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9460918 (or 9460916 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 24.

Adding to 21230221452 its reverse (25412203212), we get a palindrome (46642424664).

The spelling of 21230221452 in words is "twenty-one billion, two hundred thirty million, two hundred twenty-one thousand, four hundred fifty-two".