21934388 has 24 divisors (see below), whose sum is σ = 44057664. Its totient is φ = 9360000.

The previous prime is 21934373. The next prime is 21934399. The reversal of 21934388 is 88343912.

It is a super-2 number, since 2×21934388² = 962234753869088, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5468 + ... + 8588.

It is an arithmetic number, because the mean of its divisors is an integer number (1835736).

Almost surely, 2^21934388 is an apocalyptic number.

21934388 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21934388 is an abundant number, since it is smaller than the sum of its proper divisors (22123276).

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

21934388 is a wasteful number, since it uses less digits than its factorization.

21934388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3383 (or 3381 counting only the distinct ones).

The product of its digits is 41472, while the sum is 38.

The square root of 21934388 is about 4683.4162744732. The cubic root of 21934388 is about 279.9250990131.

It can be divided in two parts, 21934 and 388, that added together give a palindrome (22322).

The spelling of 21934388 in words is "twenty-one million, nine hundred thirty-four thousand, three hundred eighty-eight".