21427086 has 8 divisors (see below), whose sum is σ = 42854184. Its totient is φ = 7142360.

The previous prime is 21427073. The next prime is 21427097. The reversal of 21427086 is 68072412.

It is a sphenic number, since it is the product of 3 distinct primes.

21427086 is an admirable number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1785585 + ... + 1785596.

It is an arithmetic number, because the mean of its divisors is an integer number (5356773).

Almost surely, 2^21427086 is an apocalyptic number.

21427086 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21427086 is a wasteful number, since it uses less digits than its factorization.

21427086 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3571186.

The product of its (nonzero) digits is 5376, while the sum is 30.

The square root of 21427086 is about 4628.9400514589. The cubic root of 21427086 is about 277.7501939662.

Adding to 21427086 its reverse (68072412), we get a palindrome (89499498).

The spelling of 21427086 in words is "twenty-one million, four hundred twenty-seven thousand, eighty-six".