20211312 has 80 divisors (see below), whose sum is σ = 57674880. Its totient is φ = 6048000.

The previous prime is 20211263. The next prime is 20211377. The reversal of 20211312 is 21311202.

It is a super-2 number, since 2×20211312² = 816994265522688, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 53139 + ... + 53517.

It is an arithmetic number, because the mean of its divisors is an integer number (720936).

Almost surely, 2^20211312 is an apocalyptic number.

20211312 is a gapful number since it is divisible by the number (22) 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 20211312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28837440).

20211312 is an abundant number, since it is smaller than the sum of its proper divisors (37463568).

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

20211312 is a wasteful number, since it uses less digits than its factorization.

20211312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 502 (or 496 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 20211312 is about 4495.6992781991. The cubic root of 20211312 is about 272.3943961362.

Adding to 20211312 its reverse (21311202), we get a palindrome (41522514).

It can be divided in two parts, 2021 and 1312, that added together give a palindrome (3333).

The spelling of 20211312 in words is "twenty million, two hundred eleven thousand, three hundred twelve".