21167280 has 60 divisors (see below), whose sum is σ = 71089200. Its totient is φ = 5644416.

The previous prime is 21167257. The next prime is 21167297. The reversal of 21167280 is 8276112.

It is a tau number, because it is divible by the number of its divisors (60).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13980 + ... + 15419.

It is an arithmetic number, because the mean of its divisors is an integer number (1184820).

Almost surely, 2^21167280 is an apocalyptic number.

21167280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21167280 is an abundant number, since it is smaller than the sum of its proper divisors (49921920).

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

21167280 is a wasteful number, since it uses less digits than its factorization.

21167280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29418 (or 29409 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The square root of 21167280 is about 4600.7912362984. The cubic root of 21167280 is about 276.6230411367.

The spelling of 21167280 in words is "twenty-one million, one hundred sixty-seven thousand, two hundred eighty".