21280190 has 32 divisors (see below), whose sum is σ = 41195520. Its totient is φ = 7889184.

The previous prime is 21280177. The next prime is 21280201. The reversal of 21280190 is 9108212.

It is a super-2 number, since 2×21280190² = 905692972872200, 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 15 ways as a sum of consecutive naturals, for example, 7739 + ... + 10121.

It is an arithmetic number, because the mean of its divisors is an integer number (1287360).

Almost surely, 2^21280190 is an apocalyptic number.

21280190 is a deficient number, since it is larger than the sum of its proper divisors (19915330).

21280190 is a wasteful number, since it uses less digits than its factorization.

21280190 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2456.

The product of its (nonzero) digits is 288, while the sum is 23.

The square root of 21280190 is about 4613.0456316841. The cubic root of 21280190 is about 277.1140211864.

The spelling of 21280190 in words is "twenty-one million, two hundred eighty thousand, one hundred ninety".