21967400 has 192 divisors, whose sum is σ = 67495680. Its totient is φ = 6451200.

The previous prime is 21967397. The next prime is 21967403. The reversal of 21967400 is 476912.

It is an interprime number because it is at equal distance from previous prime (21967397) and next prime (21967403).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21967403) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 309365 + ... + 309435.

It is an arithmetic number, because the mean of its divisors is an integer number (351540).

Almost surely, 2^21967400 is an apocalyptic number.

21967400 is a gapful number since it is divisible by the number (20) 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 21967400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33747840).

21967400 is an abundant number, since it is smaller than the sum of its proper divisors (45528280).

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

21967400 is a wasteful number, since it uses less digits than its factorization.

21967400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124 (or 115 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 21967400 is about 4686.9392997990. The cubic root of 21967400 is about 280.0654608853.

The spelling of 21967400 in words is "twenty-one million, nine hundred sixty-seven thousand, four hundred".