20921912 has 16 divisors (see below), whose sum is σ = 42795000. Its totient is φ = 9509920.

The previous prime is 20921911. The next prime is 20921947. The reversal of 20921912 is 21912902.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20921911) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 118787 + ... + 118962.

Almost surely, 2^20921912 is an apocalyptic number.

20921912 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

20921912 is an abundant number, since it is smaller than the sum of its proper divisors (21873088).

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

20921912 is a wasteful number, since it uses less digits than its factorization.

20921912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 237766 (or 237762 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 20921912 is about 4574.0476604426. The cubic root of 20921912 is about 275.5500264336.

It can be divided in two parts, 2092 and 1912, that added together give a palindrome (4004).

The spelling of 20921912 in words is "twenty million, nine hundred twenty-one thousand, nine hundred twelve".