21286190 has 16 divisors (see below), whose sum is σ = 38610000. Its totient is φ = 8448960.

The previous prime is 21286189. The next prime is 21286229. The reversal of 21286190 is 9168212.

It is a super-2 number, since 2×21286190² = 906203769432200, 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, 6815 + ... + 9434.

It is an arithmetic number, because the mean of its divisors is an integer number (2413125).

Almost surely, 2^21286190 is an apocalyptic number.

21286190 is a deficient number, since it is larger than the sum of its proper divisors (17323810).

21286190 is a wasteful number, since it uses less digits than its factorization.

21286190 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16387.

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 21286190 is about 4613.6959154240. The cubic root of 21286190 is about 277.1400630573.

The spelling of 21286190 in words is "twenty-one million, two hundred eighty-six thousand, one hundred ninety".