21230202312 has 48 divisors (see below), whose sum is σ = 62725600080. Its totient is φ = 6433394400.

The previous prime is 21230202277. The next prime is 21230202317. The reversal of 21230202312 is 21320203212.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (21230202317) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13402114 + ... + 13403697.

It is an arithmetic number, because the mean of its divisors is an integer number (1306783335).

Almost surely, 2^21230202312 is an apocalyptic number.

21230202312 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21230202312 is an abundant number, since it is smaller than the sum of its proper divisors (41495397768).

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

21230202312 is a wasteful number, since it uses less digits than its factorization.

21230202312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26805834 (or 26805827 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

Adding to 21230202312 its reverse (21320203212), we get a palindrome (42550405524).

The spelling of 21230202312 in words is "twenty-one billion, two hundred thirty million, two hundred two thousand, three hundred twelve".