21367280 has 40 divisors (see below), whose sum is σ = 54197424. Its totient is φ = 7769600.

The previous prime is 21367243. The next prime is 21367289. The reversal of 21367280 is 8276312.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21367289) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11261 + ... + 13020.

Almost surely, 2^21367280 is an apocalyptic number.

21367280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21367280 is an abundant number, since it is smaller than the sum of its proper divisors (32830144).

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

21367280 is a wasteful number, since it uses less digits than its factorization.

21367280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24305 (or 24299 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 21367280 is about 4622.4755272473. The cubic root of 21367280 is about 277.4915399309.

The spelling of 21367280 in words is "twenty-one million, three hundred sixty-seven thousand, two hundred eighty".